68641920 has 192 divisors, whose sum is σ = 251330040. Its totient is φ = 17203200.

The previous prime is 68641883. The next prime is 68641931. The reversal of 68641920 is 2914686.

68641920 is a `hidden beast` number, since 6 + 8 + 641 + 9 + 2 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 67765824 + 876096 = 8232^2 + 936^2 .

It is a tau number, because it is divible by the number of its divisors (192).

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

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, 97570 + ... + 98270.

Almost surely, 2^68641920 is an apocalyptic number.

68641920 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 68641920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125665020).

68641920 is an abundant number, since it is smaller than the sum of its proper divisors (182688120).

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

68641920 is a wasteful number, since it uses less digits than its factorization.

68641920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 743 (or 728 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 68641920 is about 8285.0419431648. The cubic root of 68641920 is about 409.4458506045.

The spelling of 68641920 in words is "sixty-eight million, six hundred forty-one thousand, nine hundred twenty".