81347888970 has 24 divisors (see below), whose sum is σ = 211504511556. Its totient is φ = 21692770368.

The previous prime is 81347888933. The next prime is 81347888983. The reversal of 81347888970 is 7988874318.

81347888970 is a `hidden beast` number, since 8 + 13 + 478 + 8 + 89 + 70 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 78564165849 + 2783723121 = 280293^2 + 52761^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81347888898 and 81347888907.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 451932627 + ... + 451932806.

Almost surely, 2^81347888970 is an apocalyptic number.

81347888970 is an abundant number, since it is smaller than the sum of its proper divisors (130156622586).

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

81347888970 is a wasteful number, since it uses less digits than its factorization.

81347888970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 903865446 (or 903865443 counting only the distinct ones).

The product of its (nonzero) digits is 21676032, while the sum is 63.

The spelling of 81347888970 in words is "eighty-one billion, three hundred forty-seven million, eight hundred eighty-eight thousand, nine hundred seventy".