640255014421 has 4 divisors (see below), whose sum is σ = 698460015744. Its totient is φ = 582050013100.

The previous prime is 640255014379. The next prime is 640255014433. The reversal of 640255014421 is 124410552046.

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 not a de Polignac number, because 640255014421 - 2¹⁷ = 640254883349 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 (640255014481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29102500645 + ... + 29102500666.

It is an arithmetic number, because the mean of its divisors is an integer number (174615003936).

Almost surely, 2^640255014421 is an apocalyptic number.

It is an amenable number.

640255014421 is a deficient number, since it is larger than the sum of its proper divisors (58205001323).

640255014421 is a wasteful number, since it uses less digits than its factorization.

640255014421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58205001322.

The product of its (nonzero) digits is 38400, while the sum is 34.

Adding to 640255014421 its reverse (124410552046), we get a palindrome (764665566467).

The spelling of 640255014421 in words is "six hundred forty billion, two hundred fifty-five million, fourteen thousand, four hundred twenty-one".