81361896 has 64 divisors (see below), whose sum is σ = 253601280. Its totient is φ = 21132480.

The previous prime is 81361883. The next prime is 81361909. The reversal of 81361896 is 69816318.

It is an interprime number because it is at equal distance from previous prime (81361883) and next prime (81361909).

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 20166 + ... + 23861.

It is an arithmetic number, because the mean of its divisors is an integer number (3962520).

Almost surely, 2^81361896 is an apocalyptic number.

It is an amenable number.

81361896 is an abundant number, since it is smaller than the sum of its proper divisors (172239384).

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

81361896 is a wasteful number, since it uses less digits than its factorization.

81361896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44054 (or 44050 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 81361896 is about 9020.0829264481. The cubic root of 81361896 is about 433.3182895501.

The spelling of 81361896 in words is "eighty-one million, three hundred sixty-one thousand, eight hundred ninety-six".