161661275700 has 72 divisors (see below), whose sum is σ = 468034231392. Its totient is φ = 43082551680.

The previous prime is 161661275683. The next prime is 161661275707. The reversal of 161661275700 is 7572166161.

It is a super-2 number, since 2×161661275700² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161661275707) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 310387 + ... + 647813.

It is an arithmetic number, because the mean of its divisors is an integer number (6500475436).

Almost surely, 2^161661275700 is an apocalyptic number.

161661275700 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161661275700 is an abundant number, since it is smaller than the sum of its proper divisors (306372955692).

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

161661275700 is a wasteful number, since it uses less digits than its factorization.

161661275700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339041 (or 339034 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 42.

The spelling of 161661275700 in words is "one hundred sixty-one billion, six hundred sixty-one million, two hundred seventy-five thousand, seven hundred".