7721125 has 16 divisors (see below), whose sum is σ = 10146240. Its totient is φ = 5850000.

The previous prime is 7721117. The next prime is 7721143. The reversal of 7721125 is 5211277.

It is a happy number.

It is not a de Polignac number, because 7721125 - 2³ = 7721117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an Ulam number.

7721125 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 7721125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 750 + ... + 4000.

It is an arithmetic number, because the mean of its divisors is an integer number (634140).

Almost surely, 2^7721125 is an apocalyptic number.

It is an amenable number.

7721125 is a deficient number, since it is larger than the sum of its proper divisors (2425115).

7721125 is a wasteful number, since it uses less digits than its factorization.

7721125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3285 (or 3275 counting only the distinct ones).

The product of its digits is 980, while the sum is 25.

The square root of 7721125 is about 2778.6912386949. The cubic root of 7721125 is about 197.6485023157.

The spelling of 7721125 in words is "seven million, seven hundred twenty-one thousand, one hundred twenty-five".