9213972561 has 16 divisors (see below), whose sum is σ = 13729240320. Its totient is φ = 6107138640.

The previous prime is 9213972541. The next prime is 9213972571. The reversal of 9213972561 is 1652793129.

It is a happy number.

9213972561 is a `hidden beast` number, since 9 + 2 + 1 + 397 + 256 + 1 = 666.

It is not a de Polignac number, because 9213972561 - 2⁵ = 9213972529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9213972541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 981625 + ... + 990966.

It is an arithmetic number, because the mean of its divisors is an integer number (858077520).

Almost surely, 2^9213972561 is an apocalyptic number.

It is an amenable number.

9213972561 is a deficient number, since it is larger than the sum of its proper divisors (4515267759).

9213972561 is a wasteful number, since it uses less digits than its factorization.

9213972561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1972773 (or 1972767 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 9213972561 is about 95989.4398410575. The cubic root of 9213972561 is about 2096.4393600722.

The spelling of 9213972561 in words is "nine billion, two hundred thirteen million, nine hundred seventy-two thousand, five hundred sixty-one".