161511625 has 32 divisors (see below), whose sum is σ = 222258816. Its totient is φ = 116200000.

The previous prime is 161511613. The next prime is 161511641. The reversal of 161511625 is 526115161.

It is a happy number.

It is not a de Polignac number, because 161511625 - 2¹¹ = 161509577 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161511593 and 161511602.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138294 + ... + 139456.

It is an arithmetic number, because the mean of its divisors is an integer number (6945588).

Almost surely, 2^161511625 is an apocalyptic number.

It is an amenable number.

161511625 is a deficient number, since it is larger than the sum of its proper divisors (60747191).

161511625 is a wasteful number, since it uses less digits than its factorization.

161511625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290 (or 1280 counting only the distinct ones).

The product of its digits is 1800, while the sum is 28.

The square root of 161511625 is about 12708.7223984160. The cubic root of 161511625 is about 544.5878262823.

Adding to 161511625 its reverse (526115161), we get a palindrome (687626786).

The spelling of 161511625 in words is "one hundred sixty-one million, five hundred eleven thousand, six hundred twenty-five".