81007239672 has 64 divisors (see below), whose sum is σ = 231101757600. Its totient is φ = 26272615680.

The previous prime is 81007239671. The next prime is 81007239679. The reversal of 81007239672 is 27693270018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81007239671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5060029 + ... + 5076012.

Almost surely, 2^81007239672 is an apocalyptic number.

It is an amenable number.

81007239672 is an abundant number, since it is smaller than the sum of its proper divisors (150094517928).

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

81007239672 is a wasteful number, since it uses less digits than its factorization.

81007239672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10136093 (or 10136083 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The spelling of 81007239672 in words is "eighty-one billion, seven million, two hundred thirty-nine thousand, six hundred seventy-two".