640063826 has 8 divisors (see below), whose sum is σ = 1001839104. Its totient is φ = 306117460.

The previous prime is 640063819. The next prime is 640063829. The reversal of 640063826 is 628360046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (640063829) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 6957170 + ... + 6957261.

It is an arithmetic number, because the mean of its divisors is an integer number (125229888).

Almost surely, 2^640063826 is an apocalyptic number.

640063826 is a deficient number, since it is larger than the sum of its proper divisors (361775278).

640063826 is a wasteful number, since it uses less digits than its factorization.

640063826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13914456.

The product of its (nonzero) digits is 41472, while the sum is 35.

The square root of 640063826 is about 25299.4827219847. The cubic root of 640063826 is about 861.8025227581.

The spelling of 640063826 in words is "six hundred forty million, sixty-three thousand, eight hundred twenty-six".