7911921 has 8 divisors (see below), whose sum is σ = 10643040. Its totient is φ = 5227712.

The previous prime is 7911907. The next prime is 7911971. The reversal of 7911921 is 1291197.

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 7911921 - 2¹¹ = 7909873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7911971) 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, 11331 + ... + 12008.

It is an arithmetic number, because the mean of its divisors is an integer number (1330380).

Almost surely, 2^7911921 is an apocalyptic number.

It is an amenable number.

7911921 is a deficient number, since it is larger than the sum of its proper divisors (2731119).

7911921 is a wasteful number, since it uses less digits than its factorization.

7911921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23455.

The product of its digits is 1134, while the sum is 30.

The square root of 7911921 is about 2812.8137158369. The cubic root of 7911921 is about 199.2632980162.

The spelling of 7911921 in words is "seven million, nine hundred eleven thousand, nine hundred twenty-one".