64428672 has 128 divisors (see below), whose sum is σ = 213465600. Its totient is φ = 16727040.

The previous prime is 64428647. The next prime is 64428673. The reversal of 64428672 is 27682446.

It is a tau number, because it is divible by the number of its divisors (128).

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

It is a self number, because there is not a number n which added to its sum of digits gives 64428672.

It is not an unprimeable number, because it can be changed into a prime (64428673) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28479 + ... + 30657.

It is an arithmetic number, because the mean of its divisors is an integer number (1667700).

Almost surely, 2^64428672 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 64428672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106732800).

64428672 is an abundant number, since it is smaller than the sum of its proper divisors (149036928).

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

64428672 is a wasteful number, since it uses less digits than its factorization.

64428672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2214 (or 2202 counting only the distinct ones).

The product of its digits is 129024, while the sum is 39.

The square root of 64428672 is about 8026.7472864168. The cubic root of 64428672 is about 400.8910801331.

The spelling of 64428672 in words is "sixty-four million, four hundred twenty-eight thousand, six hundred seventy-two".