917671921 has 4 divisors (see below), whose sum is σ = 917773632. Its totient is φ = 917570212.

The previous prime is 917671897. The next prime is 917671927. The reversal of 917671921 is 129176719.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 917671921 - 2⁹ = 917671409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (917671927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35845 + ... + 55858.

It is an arithmetic number, because the mean of its divisors is an integer number (229443408).

Almost surely, 2^917671921 is an apocalyptic number.

It is an amenable number.

917671921 is a deficient number, since it is larger than the sum of its proper divisors (101711).

917671921 is a wasteful number, since it uses less digits than its factorization.

917671921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101710.

The product of its digits is 47628, while the sum is 43.

The square root of 917671921 is about 30293.1002210074. The cubic root of 917671921 is about 971.7677478734.

The spelling of 917671921 in words is "nine hundred seventeen million, six hundred seventy-one thousand, nine hundred twenty-one".