161555051015640 has 96 divisors (see below), whose sum is σ = 525132843459120. Its totient is φ = 43074870822144.

The previous prime is 161555051015627. The next prime is 161555051015671. The reversal of 161555051015640 is 46510150555161.

161555051015640 is a `hidden beast` number, since 1 + 6 + 1 + 5 + 550 + 5 + 1 + 0 + 1 + 56 + 40 = 666.

It is a super-2 number, since 2×161555051015640² (a number of 29 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31331362 + ... + 36121521.

Almost surely, 2^{161555051015640} is an apocalyptic number.

161555051015640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161555051015640 is an abundant number, since it is smaller than the sum of its proper divisors (363577792443480).

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

161555051015640 is a wasteful number, since it uses less digits than its factorization.

161555051015640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67459553 (or 67459546 counting only the distinct ones).

The product of its (nonzero) digits is 450000, while the sum is 45.

The spelling of 161555051015640 in words is "one hundred sixty-one trillion, five hundred fifty-five billion, fifty-one million, fifteen thousand, six hundred forty".