919163921 has 16 divisors (see below), whose sum is σ = 1009602048. Its totient is φ = 831643200.

The previous prime is 919163909. The next prime is 919163923. The reversal of 919163921 is 129361919.

It is a cyclic number.

It is not a de Polignac number, because 919163921 - 2²² = 914969617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (919163923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 244760 + ... + 248486.

It is an arithmetic number, because the mean of its divisors is an integer number (63100128).

Almost surely, 2^919163921 is an apocalyptic number.

It is an amenable number.

919163921 is a deficient number, since it is larger than the sum of its proper divisors (90438127).

919163921 is a wasteful number, since it uses less digits than its factorization.

919163921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4112.

The product of its digits is 26244, while the sum is 41.

The square root of 919163921 is about 30317.7162893250. The cubic root of 919163921 is about 972.2941133398.

The spelling of 919163921 in words is "nine hundred nineteen million, one hundred sixty-three thousand, nine hundred twenty-one".