921216511065 has 32 divisors (see below), whose sum is σ = 1515046757760. Its totient is φ = 477779434496.

The previous prime is 921216511003. The next prime is 921216511069. The reversal of 921216511065 is 560115612129.

It is a cyclic number.

It is not a de Polignac number, because 921216511065 - 2⁹ = 921216510553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (921216511069) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5037435 + ... + 5217104.

It is an arithmetic number, because the mean of its divisors is an integer number (47345211180).

Almost surely, 2^921216511065 is an apocalyptic number.

It is an amenable number.

921216511065 is a deficient number, since it is larger than the sum of its proper divisors (593830246695).

921216511065 is a wasteful number, since it uses less digits than its factorization.

921216511065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10254713.

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 921216511065 in words is "nine hundred twenty-one billion, two hundred sixteen million, five hundred eleven thousand, sixty-five".