81603272 has 16 divisors (see below), whose sum is σ = 153375900. Its totient is φ = 40703040.

The previous prime is 81603257. The next prime is 81603317. The reversal of 81603272 is 27230618.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 56942116 + 24661156 = 7546^2 + 4966^2 .

It is a super-2 number, since 2×81603272² = 13318188002211968, which contains 22 as substring.

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, 8747 + ... + 15482.

Almost surely, 2^81603272 is an apocalyptic number.

It is an amenable number.

81603272 is a deficient number, since it is larger than the sum of its proper divisors (71772628).

81603272 is a wasteful number, since it uses less digits than its factorization.

81603272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24656 (or 24652 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 81603272 is about 9033.4529389376. The cubic root of 81603272 is about 433.7463743548.

The spelling of 81603272 in words is "eighty-one million, six hundred three thousand, two hundred seventy-two".