71956521632961 has 81 divisors (see below), whose sum is σ = 121768351999203. Its totient is φ = 40826987238240.

The previous prime is 71956521632839. The next prime is 71956521632971. The reversal of 71956521632961 is 16923612565917.

The square root of 71956521632961 is 8482719.

It is a perfect power (a square), and thus also a powerful number.

71956521632961 is a `hidden beast` number, since 7 + 1 + 9 + 565 + 2 + 1 + 6 + 3 + 2 + 9 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 8430201917361 + 63526319715600 = 2903481^2 + 7970340^2 .

It is not a de Polignac number, because 71956521632961 - 2²⁵ = 71956488078529 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (71956521632971) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 26542426396 + ... + 26542429106.

Almost surely, 2^{71956521632961} is an apocalyptic number.

71956521632961 is the 8482719-th square number.

71956521632961 is the 4241360-th centered octagonal number.

It is an amenable number.

71956521632961 is a deficient number, since it is larger than the sum of its proper divisors (49811830366242).

71956521632961 is an frugal number, since it uses more digits than its factorization.

71956521632961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5740 (or 2870 counting only the distinct ones).

The product of its digits is 36741600, while the sum is 63.

The spelling of 71956521632961 in words is "seventy-one trillion, nine hundred fifty-six billion, five hundred twenty-one million, six hundred thirty-two thousand, nine hundred sixty-one".