71961530 has 16 divisors (see below), whose sum is σ = 129846024. Its totient is φ = 28714560.

The previous prime is 71961529. The next prime is 71961541. The reversal of 71961530 is 3516917.

It can be written as a sum of positive squares in 4 ways, for example, as 35153041 + 36808489 = 5929^2 + 6067^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4337 + ... + 12756.

Almost surely, 2^71961530 is an apocalyptic number.

71961530 is a deficient number, since it is larger than the sum of its proper divisors (57884494).

71961530 is a wasteful number, since it uses less digits than its factorization.

71961530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17521.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 71961530 is about 8483.0142048685. The cubic root of 71961530 is about 415.9426580541.

The spelling of 71961530 in words is "seventy-one million, nine hundred sixty-one thousand, five hundred thirty".