64666624 has 44 divisors (see below), whose sum is σ = 141046488. Its totient is φ = 29388800.

The previous prime is 64666621. The next prime is 64666643. The reversal of 64666624 is 42666646.

It is a tau number, because it is divible by the number of its divisors (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64666621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8394 + ... + 14134.

It is an arithmetic number, because the mean of its divisors is an integer number (3205602).

Almost surely, 2^64666624 is an apocalyptic number.

64666624 is a gapful number since it is divisible by the number (64) 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 64666624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70523244).

64666624 is an abundant number, since it is smaller than the sum of its proper divisors (76379864).

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

64666624 is a wasteful number, since it uses less digits than its factorization.

64666624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5772 (or 5754 counting only the distinct ones).

The product of its digits is 248832, while the sum is 40.

The square root of 64666624 is about 8041.5560683241. The cubic root of 64666624 is about 401.3840057969.

The spelling of 64666624 in words is "sixty-four million, six hundred sixty-six thousand, six hundred twenty-four".