81814831732 has 6 divisors (see below), whose sum is σ = 143175955538. Its totient is φ = 40907415864.

The previous prime is 81814831621. The next prime is 81814831757. The reversal of 81814831732 is 23713841818.

It can be written as a sum of positive squares in only one way, i.e., 62417027556 + 19397804176 = 249834^2 + 139276^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10226853963 + ... + 10226853970.

Almost surely, 2^81814831732 is an apocalyptic number.

It is an amenable number.

81814831732 is a deficient number, since it is larger than the sum of its proper divisors (61361123806).

81814831732 is a wasteful number, since it uses less digits than its factorization.

81814831732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20453707937 (or 20453707935 counting only the distinct ones).

The product of its digits is 258048, while the sum is 46.

The spelling of 81814831732 in words is "eighty-one billion, eight hundred fourteen million, eight hundred thirty-one thousand, seven hundred thirty-two".