9965606921 has 8 divisors (see below), whose sum is σ = 10303770624. Its totient is φ = 9628486560.

The previous prime is 9965606909. The next prime is 9965606927. The reversal of 9965606921 is 1296065699.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9965606921 - 2³⁰ = 8891865097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9965606927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 241385 + ... + 279638.

It is an arithmetic number, because the mean of its divisors is an integer number (1287971328).

Almost surely, 2^9965606921 is an apocalyptic number.

It is an amenable number.

9965606921 is a deficient number, since it is larger than the sum of its proper divisors (338163703).

9965606921 is a wasteful number, since it uses less digits than its factorization.

9965606921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521671.

The product of its (nonzero) digits is 1574640, while the sum is 53.

The square root of 9965606921 is about 99827.8864896979. The cubic root of 9965606921 is about 2151.9619315858.

The spelling of 9965606921 in words is "nine billion, nine hundred sixty-five million, six hundred six thousand, nine hundred twenty-one".