161857025802 has 12 divisors (see below), whose sum is σ = 350690222610. Its totient is φ = 53952341928.

The previous prime is 161857025801. The next prime is 161857025831. The reversal of 161857025802 is 208520758161.

161857025802 is a `hidden beast` number, since 1 + 6 + 18 + 57 + 0 + 2 + 580 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 146473832961 + 15383192841 = 382719^2 + 124029^2 .

It is not an unprimeable number, because it can be changed into a prime (161857025801) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4496028477 + ... + 4496028512.

Almost surely, 2^161857025802 is an apocalyptic number.

161857025802 is an abundant number, since it is smaller than the sum of its proper divisors (188833196808).

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

161857025802 is a wasteful number, since it uses less digits than its factorization.

161857025802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8992056997 (or 8992056994 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 45.

The spelling of 161857025802 in words is "one hundred sixty-one billion, eight hundred fifty-seven million, twenty-five thousand, eight hundred two".