64644156 has 60 divisors (see below), whose sum is σ = 177903880. Its totient is φ = 20412000.

The previous prime is 64644133. The next prime is 64644187. The reversal of 64644156 is 65144646.

64644156 is a `hidden beast` number, since 6 + 4 + 644 + 1 + 5 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 64644156.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 906 + ... + 11406.

Almost surely, 2^64644156 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 64644156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88951940).

64644156 is an abundant number, since it is smaller than the sum of its proper divisors (113259724).

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

64644156 is a wasteful number, since it uses less digits than its factorization.

64644156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10536 (or 10525 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 64644156 is about 8040.1589536526. The cubic root of 64644156 is about 401.3375143204.

The spelling of 64644156 in words is "sixty-four million, six hundred forty-four thousand, one hundred fifty-six".