916765621 has 4 divisors (see below), whose sum is σ = 925333632. Its totient is φ = 908197612.

The previous prime is 916765601. The next prime is 916765631. The reversal of 916765621 is 126567619.

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.

It is a cyclic number.

It is not a de Polignac number, because 916765621 - 2²³ = 908377013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (916765601) 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, 4283845 + ... + 4284058.

It is an arithmetic number, because the mean of its divisors is an integer number (231333408).

Almost surely, 2^916765621 is an apocalyptic number.

It is an amenable number.

916765621 is a deficient number, since it is larger than the sum of its proper divisors (8568011).

916765621 is a wasteful number, since it uses less digits than its factorization.

916765621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8568010.

The product of its digits is 136080, while the sum is 43.

The square root of 916765621 is about 30278.1376739059. The cubic root of 916765621 is about 971.4477340130.

The spelling of 916765621 in words is "nine hundred sixteen million, seven hundred sixty-five thousand, six hundred twenty-one".