56139840 has 168 divisors, whose sum is σ = 196019928. Its totient is φ = 14745600.

The previous prime is 56139833. The next prime is 56139859. The reversal of 56139840 is 4893165.

56139840 is a `hidden beast` number, since 561 + 3 + 98 + 4 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 11943936 + 44195904 = 3456^2 + 6648^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 56139795 and 56139804.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 290784 + ... + 290976.

Almost surely, 2^56139840 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 56139840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98009964).

56139840 is an abundant number, since it is smaller than the sum of its proper divisors (139880088).

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

56139840 is a wasteful number, since it uses less digits than its factorization.

56139840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 56139840 is about 7492.6524008525. The cubic root of 56139840 is about 382.9044293396.

It can be divided in two parts, 561 and 39840, that added together give a square (40401 = 201²).

The spelling of 56139840 in words is "fifty-six million, one hundred thirty-nine thousand, eight hundred forty".