68624640 has 432 divisors, whose sum is σ = 290803968. Its totient is φ = 14598144.

The previous prime is 68624627. The next prime is 68624641. The reversal of 68624640 is 4642686.

It is a happy number.

68624640 is a `hidden beast` number, since 6 + 8 + 6 + 2 + 4 + 640 = 666.

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 = 68624595 and 68624604.

It is not an unprimeable number, because it can be changed into a prime (68624641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1854702 + ... + 1854738.

Almost surely, 2^68624640 is an apocalyptic number.

68624640 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 68624640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145401984).

68624640 is an abundant number, since it is smaller than the sum of its proper divisors (222179328).

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

68624640 is a wasteful number, since it uses less digits than its factorization.

68624640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 68624640 is about 8283.9990342829. Note that the first 3 decimals coincide. The cubic root of 68624640 is about 409.4114895897.

The spelling of 68624640 in words is "sixty-eight million, six hundred twenty-four thousand, six hundred forty".