916921 has 4 divisors (see below), whose sum is σ = 965200. Its totient is φ = 868644.

The previous prime is 916913. The next prime is 916931. The reversal of 916921 is 129619.

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 an emirpimes, since its reverse is a distinct semiprime: 129619 = 7 ⋅18517.

It is a cyclic number.

It is not a de Polignac number, because 916921 - 2³ = 916913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 916921.

It is not an unprimeable number, because it can be changed into a prime (916931) 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, 24111 + ... + 24148.

It is an arithmetic number, because the mean of its divisors is an integer number (241300).

2⁹¹⁶⁹²¹ is an apocalyptic number.

It is an amenable number.

916921 is a deficient number, since it is larger than the sum of its proper divisors (48279).

916921 is a wasteful number, since it uses less digits than its factorization.

916921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48278.

The product of its digits is 972, while the sum is 28.

The square root of 916921 is about 957.5599197961. The cubic root of 916921 is about 97.1502613198.

The spelling of 916921 in words is "nine hundred sixteen thousand, nine hundred twenty-one".