640266415 has 4 divisors (see below), whose sum is σ = 768319704. Its totient is φ = 512213128.

The previous prime is 640266397. The next prime is 640266449. The reversal of 640266415 is 514662046.

640266415 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 640266415 - 2²⁷ = 506048687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64026637 + ... + 64026646.

It is an arithmetic number, because the mean of its divisors is an integer number (192079926).

Almost surely, 2^640266415 is an apocalyptic number.

640266415 is a deficient number, since it is larger than the sum of its proper divisors (128053289).

640266415 is a wasteful number, since it uses less digits than its factorization.

640266415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128053288.

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 640266415 is about 25303.4862222580. The cubic root of 640266415 is about 861.8934372821.

The spelling of 640266415 in words is "six hundred forty million, two hundred sixty-six thousand, four hundred fifteen".