81850560 has 224 divisors, whose sum is σ = 296704512. Its totient is φ = 18923520.

The previous prime is 81850519. The next prime is 81850579. The reversal of 81850560 is 6505818.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 242712 + ... + 243048.

Almost surely, 2^81850560 is an apocalyptic number.

81850560 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 81850560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148352256).

81850560 is an abundant number, since it is smaller than the sum of its proper divisors (214853952).

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

81850560 is a wasteful number, since it uses less digits than its factorization.

81850560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391 (or 381 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 33.

The square root of 81850560 is about 9047.1299316413. The cubic root of 81850560 is about 434.1840696693.

The spelling of 81850560 in words is "eighty-one million, eight hundred fifty thousand, five hundred sixty".