81424756 has 12 divisors (see below), whose sum is σ = 162849568. Its totient is φ = 34896312.

The previous prime is 81424751. The next prime is 81424769. The reversal of 81424756 is 65742418.

81424756 is an admirable number.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81424751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1453986 + ... + 1454041.

Almost surely, 2^81424756 is an apocalyptic number.

It is an amenable number.

81424756 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81424756 is a wasteful number, since it uses less digits than its factorization.

81424756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2908038 (or 2908036 counting only the distinct ones).

The product of its digits is 53760, while the sum is 37.

The square root of 81424756 is about 9023.5667005902. The cubic root of 81424756 is about 433.4298543704.

The spelling of 81424756 in words is "eighty-one million, four hundred twenty-four thousand, seven hundred fifty-six".