64415640 has 64 divisors (see below), whose sum is σ = 201657600. Its totient is φ = 16429952.

The previous prime is 64415627. The next prime is 64415647. The reversal of 64415640 is 4651446.

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

It is a junction number, because it is equal to n+sod(n) for n = 64415598 and 64415607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64415647) 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, 8910 + ... + 14429.

It is an arithmetic number, because the mean of its divisors is an integer number (3150900).

Almost surely, 2^64415640 is an apocalyptic number.

64415640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64415640 is an abundant number, since it is smaller than the sum of its proper divisors (137241960).

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

64415640 is a wasteful number, since it uses less digits than its factorization.

64415640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23376 (or 23372 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 64415640 is about 8025.9354594963. The cubic root of 64415640 is about 400.8640488716.

The spelling of 64415640 in words is "sixty-four million, four hundred fifteen thousand, six hundred forty".