623662663681 has 4 divisors (see below), whose sum is σ = 623677436932. Its totient is φ = 623647890432.

The previous prime is 623662663649. The next prime is 623662663691. The reversal of 623662663681 is 186366266326.

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

It can be written as a sum of positive squares in 2 ways, for example, as 541843210000 + 81819453681 = 736100^2 + 286041^2 .

It is a cyclic number.

It is not a de Polignac number, because 623662663681 - 2⁵ = 623662663649 is a prime.

It is a super-2 number, since 2×623662663681² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (623662663621) 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, 7323120 + ... + 7407793.

It is an arithmetic number, because the mean of its divisors is an integer number (155919359233).

Almost surely, 2^623662663681 is an apocalyptic number.

It is an amenable number.

623662663681 is a deficient number, since it is larger than the sum of its proper divisors (14773251).

623662663681 is a wasteful number, since it uses less digits than its factorization.

623662663681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14773250.

The product of its digits is 13436928, while the sum is 55.

The spelling of 623662663681 in words is "six hundred twenty-three billion, six hundred sixty-two million, six hundred sixty-three thousand, six hundred eighty-one".