81251044 has 48 divisors (see below), whose sum is σ = 166555648. Its totient is φ = 33965568.

The previous prime is 81251029. The next prime is 81251059. The reversal of 81251044 is 44015218.

It is an interprime number because it is at equal distance from previous prime (81251029) and next prime (81251059).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 259432 + ... + 259744.

Almost surely, 2^81251044 is an apocalyptic number.

It is an amenable number.

81251044 is an abundant number, since it is smaller than the sum of its proper divisors (85304604).

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

81251044 is a wasteful number, since it uses less digits than its factorization.

81251044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524 (or 522 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 81251044 is about 9013.9360991744. The cubic root of 81251044 is about 433.1214077469.

The spelling of 81251044 in words is "eighty-one million, two hundred fifty-one thousand, forty-four".