81497252 has 24 divisors (see below), whose sum is σ = 153865656. Its totient is φ = 37626368.

The previous prime is 81497243. The next prime is 81497261. The reversal of 81497252 is 25279418.

It is an interprime number because it is at equal distance from previous prime (81497243) and next prime (81497261).

It can be written as a sum of positive squares in 4 ways, for example, as 27709696 + 53787556 = 5264^2 + 7334^2 .

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 7 ways as a sum of consecutive naturals, for example, 7703 + ... + 14910.

It is an arithmetic number, because the mean of its divisors is an integer number (6411069).

Almost surely, 2^81497252 is an apocalyptic number.

It is an amenable number.

81497252 is a deficient number, since it is larger than the sum of its proper divisors (72368404).

81497252 is a wasteful number, since it uses less digits than its factorization.

81497252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22687 (or 22685 counting only the distinct ones).

The product of its digits is 40320, while the sum is 38.

The square root of 81497252 is about 9027.5828437074. The cubic root of 81497252 is about 433.5584500270.

The spelling of 81497252 in words is "eighty-one million, four hundred ninety-seven thousand, two hundred fifty-two".