6521340431256 has 64 divisors (see below), whose sum is σ = 19135979662080. Its totient is φ = 1812882280320.

The previous prime is 6521340431251. The next prime is 6521340431257.

6521340431256 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6521340431251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 524554630 + ... + 524567061.

It is an arithmetic number, because the mean of its divisors is an integer number (298999682220).

Almost surely, 2^{6521340431256} is an apocalyptic number.

It is an amenable number.

6521340431256 is an abundant number, since it is smaller than the sum of its proper divisors (12614639230824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6521340431256 is a wasteful number, since it uses less digits than its factorization.

6521340431256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049121744 (or 1049121740 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 42.

It can be divided in two parts, 6521340 and 431256, that added together give a palindrome (6952596).

The spelling of 6521340431256 in words is "six trillion, five hundred twenty-one billion, three hundred forty million, four hundred thirty-one thousand, two hundred fifty-six".