161886188900 has 18 divisors (see below), whose sum is σ = 351293030130. Its totient is φ = 64754475520.

The previous prime is 161886188897. The next prime is 161886188929. The reversal of 161886188900 is 9881688161.

It can be written as a sum of positive squares in 3 ways, for example, as 10317683776 + 151568505124 = 101576^2 + 389318^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 809430845 + ... + 809431044.

Almost surely, 2^161886188900 is an apocalyptic number.

161886188900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161886188900 is an abundant number, since it is smaller than the sum of its proper divisors (189406841230).

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

161886188900 is a wasteful number, since it uses less digits than its factorization.

161886188900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1618861903 (or 1618861896 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 56.

The spelling of 161886188900 in words is "one hundred sixty-one billion, eight hundred eighty-six million, one hundred eighty-eight thousand, nine hundred".