81902560 has 24 divisors (see below), whose sum is σ = 193495176. Its totient is φ = 32760960.

The previous prime is 81902533. The next prime is 81902567. The reversal of 81902560 is 6520918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81902567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 255786 + ... + 256105.

It is an arithmetic number, because the mean of its divisors is an integer number (8062299).

Almost surely, 2^81902560 is an apocalyptic number.

81902560 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81902560 is an abundant number, since it is smaller than the sum of its proper divisors (111592616).

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

81902560 is a wasteful number, since it uses less digits than its factorization.

81902560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511906 (or 511898 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 81902560 is about 9050.0033149165. The cubic root of 81902560 is about 434.2759965178.

The spelling of 81902560 in words is "eighty-one million, nine hundred two thousand, five hundred sixty".