81279296572 has 12 divisors (see below), whose sum is σ = 142828973056. Its totient is φ = 40471018560.

The previous prime is 81279296519. The next prime is 81279296587. The reversal of 81279296572 is 27569297218.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42156348 + ... + 42158275.

Almost surely, 2^81279296572 is an apocalyptic number.

It is an amenable number.

81279296572 is a deficient number, since it is larger than the sum of its proper divisors (61549676484).

81279296572 is a wasteful number, since it uses less digits than its factorization.

81279296572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84314868 (or 84314866 counting only the distinct ones).

The product of its digits is 7620480, while the sum is 58.

The spelling of 81279296572 in words is "eighty-one billion, two hundred seventy-nine million, two hundred ninety-six thousand, five hundred seventy-two".