7857920 has 72 divisors (see below), whose sum is σ = 21535584. Its totient is φ = 2691072.

The previous prime is 7857917. The next prime is 7857943. The reversal of 7857920 is 297587.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8522 + ... + 9398.

Almost surely, 2^7857920 is an apocalyptic number.

7857920 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7857920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10767792).

7857920 is an abundant number, since it is smaller than the sum of its proper divisors (13677664).

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

7857920 is an equidigital number, since it uses as much as digits as its factorization.

7857920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905 (or 891 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 38.

The square root of 7857920 is about 2803.1981735154. The cubic root of 7857920 is about 198.8089207321.

The spelling of 7857920 in words is "seven million, eight hundred fifty-seven thousand, nine hundred twenty".