640254155213 has 4 divisors (see below), whose sum is σ = 640956959808. Its totient is φ = 639551350620.

The previous prime is 640254155207. The next prime is 640254155221. The reversal of 640254155213 is 312551452046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640254155213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640254155273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351400931 + ... + 351402752.

It is an arithmetic number, because the mean of its divisors is an integer number (160239239952).

Almost surely, 2^640254155213 is an apocalyptic number.

It is an amenable number.

640254155213 is a deficient number, since it is larger than the sum of its proper divisors (702804595).

640254155213 is an equidigital number, since it uses as much as digits as its factorization.

640254155213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702804594.

The product of its (nonzero) digits is 144000, while the sum is 38.

The spelling of 640254155213 in words is "six hundred forty billion, two hundred fifty-four million, one hundred fifty-five thousand, two hundred thirteen".