161739325440 has 1620 divisors, whose sum is σ = 736277242428. Its totient is φ = 32699842560.

The previous prime is 161739325427. The next prime is 161739325457. The reversal of 161739325440 is 44523937161.

161739325440 is a `hidden beast` number, since 1 + 6 + 1 + 7 + 393 + 254 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 105786261504 + 55953063936 = 325248^2 + 236544^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 4371333102 + ... + 4371333138.

Almost surely, 2^161739325440 is an apocalyptic number.

161739325440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161739325440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (368138621214).

161739325440 is an abundant number, since it is smaller than the sum of its proper divisors (574537916988).

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

161739325440 is a wasteful number, since it uses less digits than its factorization.

161739325440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 45.

The spelling of 161739325440 in words is "one hundred sixty-one billion, seven hundred thirty-nine million, three hundred twenty-five thousand, four hundred forty".