640256144212 has 24 divisors (see below), whose sum is σ = 1136550441600. Its totient is φ = 315529996320.

The previous prime is 640256144207. The next prime is 640256144237. The reversal of 640256144212 is 212441652046.

It is a super-2 number, since 2×640256144212² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 693289 + ... + 1327087.

It is an arithmetic number, because the mean of its divisors is an integer number (47356268400).

Almost surely, 2^640256144212 is an apocalyptic number.

It is an amenable number.

640256144212 is a deficient number, since it is larger than the sum of its proper divisors (496294297388).

640256144212 is a wasteful number, since it uses less digits than its factorization.

640256144212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637431 (or 637429 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 37.

Adding to 640256144212 its reverse (212441652046), we get a palindrome (852697796258).

The spelling of 640256144212 in words is "six hundred forty billion, two hundred fifty-six million, one hundred forty-four thousand, two hundred twelve".