621944435501 has 4 divisors (see below), whose sum is σ = 625418985600. Its totient is φ = 618469885404.

The previous prime is 621944435491. The next prime is 621944435513. The reversal of 621944435501 is 105534449126.

It is a happy number.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-621944435501 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621944435531) 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, 1737274781 + ... + 1737275138.

It is an arithmetic number, because the mean of its divisors is an integer number (156354746400).

Almost surely, 2^621944435501 is an apocalyptic number.

It is an amenable number.

621944435501 is a deficient number, since it is larger than the sum of its proper divisors (3474550099).

621944435501 is a wasteful number, since it uses less digits than its factorization.

621944435501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3474550098.

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 621944435501 in words is "six hundred twenty-one billion, nine hundred forty-four million, four hundred thirty-five thousand, five hundred one".