81904716100 has 27 divisors (see below), whose sum is σ = 177739444477. Its totient is φ = 32760741680.

The previous prime is 81904716079. The next prime is 81904716181. The reversal of 81904716100 is 161740918.

The square root of 81904716100 is 286190.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 29485697796 + 52419018304 = 171714^2 + 228952^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81904716100.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2847591 + ... + 2876209.

Almost surely, 2^81904716100 is an apocalyptic number.

81904716100 is the 286190-th square number.

It is an amenable number.

81904716100 is an abundant number, since it is smaller than the sum of its proper divisors (95834728377).

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

81904716100 is an frugal number, since it uses more digits than its factorization.

81904716100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57252 (or 28626 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 37.

The spelling of 81904716100 in words is "eighty-one billion, nine hundred four million, seven hundred sixteen thousand, one hundred".