64660020 has 48 divisors (see below), whose sum is σ = 182374080. Its totient is φ = 17116416.

The previous prime is 64660019. The next prime is 64660039. The reversal of 64660020 is 2006646.

64660020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4464 + ... + 12216.

It is an arithmetic number, because the mean of its divisors is an integer number (3799460).

Almost surely, 2^64660020 is an apocalyptic number.

64660020 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 64660020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91187040).

64660020 is an abundant number, since it is smaller than the sum of its proper divisors (117714060).

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

64660020 is a wasteful number, since it uses less digits than its factorization.

64660020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7904 (or 7902 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 64660020 is about 8041.1454407939. The cubic root of 64660020 is about 401.3703417146.

Adding to 64660020 its reverse (2006646), we get a palindrome (66666666).

The spelling of 64660020 in words is "sixty-four million, six hundred sixty thousand, twenty".