81273264 has 40 divisors (see below), whose sum is σ = 210909120. Its totient is φ = 26968128.

The previous prime is 81273263. The next prime is 81273301. The reversal of 81273264 is 46237218.

It is not an unprimeable number, because it can be changed into a prime (81273263) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7167 + ... + 14625.

It is an arithmetic number, because the mean of its divisors is an integer number (5272728).

Almost surely, 2^81273264 is an apocalyptic number.

It is an amenable number.

81273264 is an abundant number, since it is smaller than the sum of its proper divisors (129635856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81273264 is a wasteful number, since it uses less digits than its factorization.

81273264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7697 (or 7691 counting only the distinct ones).

The product of its digits is 16128, while the sum is 33.

The square root of 81273264 is about 9015.1685508370. The cubic root of 81273264 is about 433.1608865443.

The spelling of 81273264 in words is "eighty-one million, two hundred seventy-three thousand, two hundred sixty-four".