81970492 has 12 divisors (see below), whose sum is σ = 143559136. Its totient is φ = 40953600.

The previous prime is 81970477. The next prime is 81970531. The reversal of 81970492 is 29407918.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1509 + ... + 12892.

Almost surely, 2^81970492 is an apocalyptic number.

It is an amenable number.

81970492 is a deficient number, since it is larger than the sum of its proper divisors (61588644).

81970492 is a wasteful number, since it uses less digits than its factorization.

81970492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15828 (or 15826 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 81970492 is about 9053.7556847973. The cubic root of 81970492 is about 434.3960297394.

The spelling of 81970492 in words is "eighty-one million, nine hundred seventy thousand, four hundred ninety-two".