81417960 has 160 divisors (see below), whose sum is σ = 294857640. Its totient is φ = 20030976.

The previous prime is 81417949. The next prime is 81417991. The reversal of 81417960 is 6971418.

It can be written as a sum of positive squares in 4 ways, for example, as 57972996 + 23444964 = 7614^2 + 4842^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 41154 + ... + 43086.

Almost surely, 2^81417960 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81417960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147428820).

81417960 is an abundant number, since it is smaller than the sum of its proper divisors (213439680).

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

81417960 is a wasteful number, since it uses less digits than its factorization.

81417960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1969 (or 1956 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 81417960 is about 9023.1901232325. The cubic root of 81417960 is about 433.4177955020.

The spelling of 81417960 in words is "eighty-one million, four hundred seventeen thousand, nine hundred sixty".