7725222921 has 16 divisors (see below), whose sum is σ = 11350598336. Its totient is φ = 4643424576.

The previous prime is 7725222917. The next prime is 7725222961. The reversal of 7725222921 is 1292225277.

It is not a de Polignac number, because 7725222921 - 2² = 7725222917 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

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 7725222921.

It is not an unprimeable number, because it can be changed into a prime (7725222961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2301610 + ... + 2304963.

It is an arithmetic number, because the mean of its divisors is an integer number (709412396).

Almost surely, 2^7725222921 is an apocalyptic number.

It is an amenable number.

7725222921 is a deficient number, since it is larger than the sum of its proper divisors (3625375415).

7725222921 is a wasteful number, since it uses less digits than its factorization.

7725222921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4606632.

The product of its digits is 70560, while the sum is 39.

The square root of 7725222921 is about 87893.2473003473. The cubic root of 7725222921 is about 1976.8346288169.

The spelling of 7725222921 in words is "seven billion, seven hundred twenty-five million, two hundred twenty-two thousand, nine hundred twenty-one".