640209053 has 8 divisors (see below), whose sum is σ = 708834720. Its totient is φ = 573320880.

The previous prime is 640209049. The next prime is 640209067. The reversal of 640209053 is 350902046.

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

It is not a de Polignac number, because 640209053 - 2² = 640209049 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640209023) 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 7 ways as a sum of consecutive naturals, for example, 433598 + ... + 435071.

It is an arithmetic number, because the mean of its divisors is an integer number (88604340).

Almost surely, 2^640209053 is an apocalyptic number.

It is an amenable number.

640209053 is a deficient number, since it is larger than the sum of its proper divisors (68625667).

640209053 is a wasteful number, since it uses less digits than its factorization.

640209053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868747.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 640209053 is about 25302.3527166942. The cubic root of 640209053 is about 861.8676972637.

The spelling of 640209053 in words is "six hundred forty million, two hundred nine thousand, fifty-three".