816978923 has 8 divisors (see below), whose sum is σ = 845486400. Its totient is φ = 788493888.

The previous prime is 816978913. The next prime is 816978931. The reversal of 816978923 is 329879618.

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 816978923 - 2¹² = 816974827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816978913) 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, 107183 + ... + 114551.

It is an arithmetic number, because the mean of its divisors is an integer number (105685800).

Almost surely, 2^816978923 is an apocalyptic number.

816978923 is a deficient number, since it is larger than the sum of its proper divisors (28507477).

816978923 is a wasteful number, since it uses less digits than its factorization.

816978923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11221.

The product of its digits is 1306368, while the sum is 53.

The square root of 816978923 is about 28582.8431580905. The cubic root of 816978923 is about 934.8392769007.

The spelling of 816978923 in words is "eight hundred sixteen million, nine hundred seventy-eight thousand, nine hundred twenty-three".