621563243644 has 18 divisors (see below), whose sum is σ = 1265325174960. Its totient is φ = 266384247192.

The previous prime is 621563243641. The next prime is 621563243681. The reversal of 621563243644 is 446342365126.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 621563243594 and 621563243603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621563243641) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1585620324 + ... + 1585620715.

Almost surely, 2^621563243644 is an apocalyptic number.

It is an amenable number.

621563243644 is an abundant number, since it is smaller than the sum of its proper divisors (643761931316).

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

621563243644 is a wasteful number, since it uses less digits than its factorization.

621563243644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3171241057 (or 3171241048 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 46.

The spelling of 621563243644 in words is "six hundred twenty-one billion, five hundred sixty-three million, two hundred forty-three thousand, six hundred forty-four".