71808961 has 24 divisors (see below), whose sum is σ = 88728480. Its totient is φ = 57782592.

The previous prime is 71808949. The next prime is 71808977. The reversal of 71808961 is 16980817.

It is a de Polignac number, because none of the positive numbers 2^k-71808961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (71808941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 127266 + ... + 127828.

It is an arithmetic number, because the mean of its divisors is an integer number (3697020).

Almost surely, 2^71808961 is an apocalyptic number.

It is an amenable number.

71808961 is a deficient number, since it is larger than the sum of its proper divisors (16919519).

71808961 is a wasteful number, since it uses less digits than its factorization.

71808961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 733 (or 726 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 40.

The square root of 71808961 is about 8474.0168161268. The cubic root of 71808961 is about 415.6484969172.

The spelling of 71808961 in words is "seventy-one million, eight hundred eight thousand, nine hundred sixty-one".