64632720 has 80 divisors (see below), whose sum is σ = 203236992. Its totient is φ = 16988160.

The previous prime is 64632719. The next prime is 64632721. The reversal of 64632720 is 2723646.

It is an interprime number because it is at equal distance from previous prime (64632719) and next prime (64632721).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (64632721) 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, 15144 + ... + 18936.

Almost surely, 2^64632720 is an apocalyptic number.

64632720 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 64632720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101618496).

64632720 is an abundant number, since it is smaller than the sum of its proper divisors (138604272).

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

64632720 is a wasteful number, since it uses less digits than its factorization.

64632720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3880 (or 3874 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 30.

The square root of 64632720 is about 8039.4477422271. The cubic root of 64632720 is about 401.3138464605.

The spelling of 64632720 in words is "sixty-four million, six hundred thirty-two thousand, seven hundred twenty".