9961525972 has 18 divisors (see below), whose sum is σ = 18518444462. Its totient is φ = 4687776384.

The previous prime is 9961525943. The next prime is 9961525991. The reversal of 9961525972 is 2795251699.

It can be written as a sum of positive squares in 3 ways, for example, as 2186871696 + 7774654276 = 46764^2 + 88174^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4307463 + ... + 4309774.

Almost surely, 2^9961525972 is an apocalyptic number.

It is an amenable number.

9961525972 is a deficient number, since it is larger than the sum of its proper divisors (8556918490).

9961525972 is a wasteful number, since it uses less digits than its factorization.

9961525972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8617275 (or 8617256 counting only the distinct ones).

The product of its digits is 3061800, while the sum is 55.

The square root of 9961525972 is about 99807.4444718429. Note that the first 4 decimals coincide. The cubic root of 9961525972 is about 2151.6681463036.

The spelling of 9961525972 in words is "nine billion, nine hundred sixty-one million, five hundred twenty-five thousand, nine hundred seventy-two".