616921920 has 140 divisors (see below), whose sum is σ = 2194592004. Its totient is φ = 164505600.

The previous prime is 616921897. The next prime is 616921951. The reversal of 616921920 is 29129616.

616921920 is a `hidden beast` number, since 616 + 9 + 2 + 19 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 345067776 + 271854144 = 18576^2 + 16488^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 14020 + ... + 37820.

Almost surely, 2^616921920 is an apocalyptic number.

616921920 is a gapful number since it is divisible by the number (60) 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 616921920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1097296002).

616921920 is an abundant number, since it is smaller than the sum of its proper divisors (1577670084).

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

616921920 is a wasteful number, since it uses less digits than its factorization.

616921920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23830 (or 23811 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 616921920 is about 24837.9129558021. The cubic root of 616921920 is about 851.2884358433.

The spelling of 616921920 in words is "six hundred sixteen million, nine hundred twenty-one thousand, nine hundred twenty".