7720920 has 80 divisors (see below), whose sum is σ = 25961760. Its totient is φ = 2058048.

The previous prime is 7720903. The next prime is 7720943. The reversal of 7720920 is 290277.

It is a super-2 number, since 2×7720920² = 119225211292800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2049 + ... + 4431.

It is an arithmetic number, because the mean of its divisors is an integer number (324522).

Almost surely, 2^7720920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7720920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12980880).

7720920 is an abundant number, since it is smaller than the sum of its proper divisors (18240840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7720920 is a wasteful number, since it uses less digits than its factorization.

7720920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2406 (or 2393 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 7720920 is about 2778.6543505805. The cubic root of 7720920 is about 197.6467530758.

The spelling of 7720920 in words is "seven million, seven hundred twenty thousand, nine hundred twenty".