916821923 has 4 divisors (see below), whose sum is σ = 916921320. Its totient is φ = 916722528.

The previous prime is 916821889. The next prime is 916821943. The reversal of 916821923 is 329128619.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 329128619 = 17 ⋅19360507.

It is a cyclic number.

It is not a de Polignac number, because 916821923 - 2⁸ = 916821667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (916821943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34265 + ... + 54842.

It is an arithmetic number, because the mean of its divisors is an integer number (229230330).

Almost surely, 2^916821923 is an apocalyptic number.

916821923 is a deficient number, since it is larger than the sum of its proper divisors (99397).

916821923 is a wasteful number, since it uses less digits than its factorization.

916821923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99396.

The product of its digits is 46656, while the sum is 41.

The square root of 916821923 is about 30279.0674063783. The cubic root of 916821923 is about 971.4676203501.

The spelling of 916821923 in words is "nine hundred sixteen million, eight hundred twenty-one thousand, nine hundred twenty-three".