81305796 has 48 divisors (see below), whose sum is σ = 222884928. Its totient is φ = 22742400.

The previous prime is 81305789. The next prime is 81305797. The reversal of 81305796 is 69750318.

It is a super-2 number, since 2×81305796² = 13221264926387232, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (81305797) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21975 + ... + 25406.

It is an arithmetic number, because the mean of its divisors is an integer number (4643436).

Almost surely, 2^81305796 is an apocalyptic number.

It is an amenable number.

81305796 is an abundant number, since it is smaller than the sum of its proper divisors (141579132).

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

81305796 is a wasteful number, since it uses less digits than its factorization.

81305796 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47412 (or 47410 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 39.

The square root of 81305796 is about 9016.9726627067. The cubic root of 81305796 is about 433.2186739375.

The spelling of 81305796 in words is "eighty-one million, three hundred five thousand, seven hundred ninety-six".