81896286972 has 24 divisors (see below), whose sum is σ = 191096112592. Its totient is φ = 27298080000.

The previous prime is 81896286907. The next prime is 81896286973. The reversal of 81896286972 is 27968269818.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81896286973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 715722 + ... + 822222.

Almost surely, 2^81896286972 is an apocalyptic number.

It is an amenable number.

81896286972 is an abundant number, since it is smaller than the sum of its proper divisors (109199825620).

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

81896286972 is a wasteful number, since it uses less digits than its factorization.

81896286972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170589 (or 170587 counting only the distinct ones).

The product of its digits is 41803776, while the sum is 66.

The spelling of 81896286972 in words is "eighty-one billion, eight hundred ninety-six million, two hundred eighty-six thousand, nine hundred seventy-two".