81894900 has 36 divisors (see below), whose sum is σ = 236950112. Its totient is φ = 21838560.

The previous prime is 81894893. The next prime is 81894937. The reversal of 81894900 is 949818.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136192 + ... + 136791.

Almost surely, 2^81894900 is an apocalyptic number.

It is an amenable number.

81894900 is an abundant number, since it is smaller than the sum of its proper divisors (155055212).

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

81894900 is a wasteful number, since it uses less digits than its factorization.

81894900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273000 (or 272993 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 39.

The square root of 81894900 is about 9049.5801007561. The cubic root of 81894900 is about 434.2624574300.

The spelling of 81894900 in words is "eighty-one million, eight hundred ninety-four thousand, nine hundred".