81373252 has 12 divisors (see below), whose sum is σ = 142946496. Its totient is φ = 40531400.

The previous prime is 81373247. The next prime is 81373261. The reversal of 81373252 is 25237318.

It is a super-2 number, since 2×81373252² = 13243212282111008, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37624 + ... + 39727.

It is an arithmetic number, because the mean of its divisors is an integer number (11912208).

Almost surely, 2^81373252 is an apocalyptic number.

It is an amenable number.

81373252 is a deficient number, since it is larger than the sum of its proper divisors (61573244).

81373252 is a wasteful number, since it uses less digits than its factorization.

81373252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77618 (or 77616 counting only the distinct ones).

The product of its digits is 10080, while the sum is 31.

The square root of 81373252 is about 9020.7123887196. The cubic root of 81373252 is about 433.3384485918.

The spelling of 81373252 in words is "eighty-one million, three hundred seventy-three thousand, two hundred fifty-two".