64020915 has 64 divisors (see below), whose sum is σ = 133662720. Its totient is φ = 28460160.

The previous prime is 64020911. The next prime is 64020917. The reversal of 64020915 is 51902046.

64020915 is a `hidden beast` number, since 640 + 2 + 0 + 9 + 15 = 666.

It is not a de Polignac number, because 64020915 - 2² = 64020911 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (64020911) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 34050 + ... + 35880.

It is an arithmetic number, because the mean of its divisors is an integer number (2088480).

Almost surely, 2^64020915 is an apocalyptic number.

64020915 is an abundant number, since it is smaller than the sum of its proper divisors (69641805).

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

64020915 is a wasteful number, since it uses less digits than its factorization.

64020915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1889 (or 1883 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 64020915 is about 8001.3070807212. The cubic root of 64020915 is about 400.0435681710.

The spelling of 64020915 in words is "sixty-four million, twenty thousand, nine hundred fifteen".