521140442663640 has 128 divisors (see below), whose sum is σ = 1572394665470400. Its totient is φ = 138173954457600.

The previous prime is 521140442663597. The next prime is 521140442663683. The reversal of 521140442663640 is 46366244041125.

It is an interprime number because it is at equal distance from previous prime (521140442663597) and next prime (521140442663683).

It is a self number, because there is not a number n which added to its sum of digits gives 521140442663640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35464146 + ... + 47958174.

Almost surely, 2^{521140442663640} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521140442663640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (786197332735200).

521140442663640 is an abundant number, since it is smaller than the sum of its proper divisors (1051254222806760).

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

521140442663640 is a wasteful number, since it uses less digits than its factorization.

521140442663640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12496037 (or 12496033 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 48.

The spelling of 521140442663640 in words is "five hundred twenty-one trillion, one hundred forty billion, four hundred forty-two million, six hundred sixty-three thousand, six hundred forty".