621605472681 has 4 divisors (see below), whose sum is σ = 828807296912. Its totient is φ = 414403648452.

The previous prime is 621605472679. The next prime is 621605472701. The reversal of 621605472681 is 186274506126.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 621605472681 - 2¹ = 621605472679 is a prime.

It is a super-2 number, since 2×621605472681² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 621605472681.

It is not an unprimeable number, because it can be changed into a prime (621605471681) 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, 103600912111 + ... + 103600912116.

It is an arithmetic number, because the mean of its divisors is an integer number (207201824228).

Almost surely, 2^621605472681 is an apocalyptic number.

It is an amenable number.

621605472681 is a deficient number, since it is larger than the sum of its proper divisors (207201824231).

621605472681 is a wasteful number, since it uses less digits than its factorization.

621605472681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207201824230.

The product of its (nonzero) digits is 967680, while the sum is 48.

The spelling of 621605472681 in words is "six hundred twenty-one billion, six hundred five million, four hundred seventy-two thousand, six hundred eighty-one".