81057600 has 252 divisors, whose sum is σ = 310975756. Its totient is φ = 19906560.

The previous prime is 81057583. The next prime is 81057637. The reversal of 81057600 is 675018.

81057600 is a `hidden beast` number, since 8 + 1 + 0 + 57 + 600 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 22810176 + 58247424 = 4776^2 + 7632^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 186984 + ... + 187416.

Almost surely, 2^81057600 is an apocalyptic number.

81057600 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81057600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155487878).

81057600 is an abundant number, since it is smaller than the sum of its proper divisors (229918156).

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

81057600 is a wasteful number, since it uses less digits than its factorization.

81057600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474 (or 456 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 81057600 is about 9003.1994313133. The cubic root of 81057600 is about 432.7774067608. Note that the first 3 decimals are identical.

It can be divided in two parts, 810 and 57600, that multiplied together give a cube (46656000 = 360³).

The spelling of 81057600 in words is "eighty-one million, fifty-seven thousand, six hundred".