81427900 has 18 divisors (see below), whose sum is σ = 176698760. Its totient is φ = 32571120.

The previous prime is 81427877. The next prime is 81427919. The reversal of 81427900 is 972418.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 407040 + ... + 407239.

Almost surely, 2^81427900 is an apocalyptic number.

It is an amenable number.

81427900 is an abundant number, since it is smaller than the sum of its proper divisors (95270860).

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

81427900 is a wasteful number, since it uses less digits than its factorization.

81427900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814293 (or 814286 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 81427900 is about 9023.7409094012. The cubic root of 81427900 is about 433.4354328782.

The spelling of 81427900 in words is "eighty-one million, four hundred twenty-seven thousand, nine hundred".