161302640625 has 441 divisors, whose sum is σ = 373557855117. Its totient is φ = 69400800000.

The previous prime is 161302640623. The next prime is 161302640651. The reversal of 161302640625 is 526046203161.

The square root of 161302640625 is 401625.

It is a perfect power (a square), and thus also a powerful number.

161302640625 is a `hidden beast` number, since 1 + 6 + 1 + 3 + 0 + 2 + 640 + 6 + 2 + 5 = 666.

It can be written as a sum of positive squares in 10 ways, for example, as 158581557729 + 2721082896 = 398223^2 + 52164^2 .

It is a tau number, because it is divible by the number of its divisors (441).

It is not a de Polignac number, because 161302640625 - 2¹ = 161302640623 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 161302640625.

It is not an unprimeable number, because it can be changed into a prime (161302640623) by changing a digit.

It is a polite number, since it can be written in 440 ways as a sum of consecutive naturals, for example, 9488390617 + ... + 9488390633.

Almost surely, 2^161302640625 is an apocalyptic number.

161302640625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161302640625 is the 401625-th square number.

161302640625 is the 200813-rd centered octagonal number.

It is an amenable number.

161302640625 is an abundant number, since it is smaller than the sum of its proper divisors (212255214492).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161302640625 is an frugal number, since it uses more digits than its factorization.

161302640625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 32 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

Multiplying 161302640625 by its sum of digits (36), we get a square (5806895062500 = 2409750²).

Adding to 161302640625 its reverse (526046203161), we get a palindrome (687348843786).

The spelling of 161302640625 in words is "one hundred sixty-one billion, three hundred two million, six hundred forty thousand, six hundred twenty-five".