81907080 has 64 divisors (see below), whose sum is σ = 246317760. Its totient is φ = 21788928.

The previous prime is 81907051. The next prime is 81907093. The reversal of 81907080 is 8070918.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92319 + ... + 93201.

It is an arithmetic number, because the mean of its divisors is an integer number (3848715).

Almost surely, 2^81907080 is an apocalyptic number.

It is an amenable number.

81907080 is an abundant number, since it is smaller than the sum of its proper divisors (164410680).

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

81907080 is a wasteful number, since it uses less digits than its factorization.

81907080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1670 (or 1666 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 33.

The square root of 81907080 is about 9050.2530351366. The cubic root of 81907080 is about 434.2839852441.

Adding to 81907080 its reverse (8070918), we get a palindrome (89977998).

The spelling of 81907080 in words is "eighty-one million, nine hundred seven thousand, eighty".