81497611682 has 4 divisors (see below), whose sum is σ = 122246417526. Its totient is φ = 40748805840.

The previous prime is 81497611619. The next prime is 81497611691. The reversal of 81497611682 is 28611679418.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 80525980441 + 971631241 = 283771^2 + 31171^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20374402919 + ... + 20374402922.

Almost surely, 2^81497611682 is an apocalyptic number.

81497611682 is a deficient number, since it is larger than the sum of its proper divisors (40748805844).

81497611682 is a wasteful number, since it uses less digits than its factorization.

81497611682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40748805843.

The product of its digits is 1161216, while the sum is 53.

The spelling of 81497611682 in words is "eighty-one billion, four hundred ninety-seven million, six hundred eleven thousand, six hundred eighty-two".