663521315356231 has 4 divisors (see below), whose sum is σ = 665525911475464. Its totient is φ = 661516719237000.

The previous prime is 663521315356181. The next prime is 663521315356279. The reversal of 663521315356231 is 132653513125366.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-663521315356231 is a prime.

It is a super-2 number, since 2×663521315356231² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663521315306231) 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, 1002298059120 + ... + 1002298059781.

It is an arithmetic number, because the mean of its divisors is an integer number (166381477868866).

Almost surely, 2^{663521315356231} is an apocalyptic number.

663521315356231 is a deficient number, since it is larger than the sum of its proper divisors (2004596119233).

663521315356231 is a wasteful number, since it uses less digits than its factorization.

663521315356231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004596119232.

The product of its digits is 8748000, while the sum is 52.

The spelling of 663521315356231 in words is "six hundred sixty-three trillion, five hundred twenty-one billion, three hundred fifteen million, three hundred fifty-six thousand, two hundred thirty-one".