7722991 has 6 divisors (see below), whose sum is σ = 7801400. Its totient is φ = 7645176.

The previous prime is 7722983. The next prime is 7723003. The reversal of 7722991 is 1992277.

It is not a de Polignac number, because 7722991 - 2³ = 7722983 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7722991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7722931) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38710 + ... + 38908.

Almost surely, 2^7722991 is an apocalyptic number.

7722991 is a deficient number, since it is larger than the sum of its proper divisors (78409).

7722991 is an equidigital number, since it uses as much as digits as its factorization.

7722991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 593 (or 396 counting only the distinct ones).

The product of its digits is 15876, while the sum is 37.

The square root of 7722991 is about 2779.0269879942. The cubic root of 7722991 is about 197.6644232426.

The spelling of 7722991 in words is "seven million, seven hundred twenty-two thousand, nine hundred ninety-one".