64393992 has 96 divisors (see below), whose sum is σ = 190171800. Its totient is φ = 19565568.

The previous prime is 64393939. The next prime is 64394041. The reversal of 64393992 is 29939346.

It can be written as a sum of positive squares in 4 ways, for example, as 17690436 + 46703556 = 4206^2 + 6834^2 .

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

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, 82918 + ... + 83690.

Almost surely, 2^64393992 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 64393992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95085900).

64393992 is an abundant number, since it is smaller than the sum of its proper divisors (125777808).

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

64393992 is a wasteful number, since it uses less digits than its factorization.

64393992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887 (or 880 counting only the distinct ones).

The product of its digits is 314928, while the sum is 45.

The square root of 64393992 is about 8024.5867183301. The cubic root of 64393992 is about 400.8191380537.

The spelling of 64393992 in words is "sixty-four million, three hundred ninety-three thousand, nine hundred ninety-two".