646264206621 has 36 divisors (see below), whose sum is σ = 1026163325824. Its totient is φ = 391639857840.

The previous prime is 646264206617. The next prime is 646264206631. The reversal of 646264206621 is 126602462646.

646264206621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 646264206621 - 2² = 646264206617 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 (646264206631) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 16950846 + ... + 16988928.

Almost surely, 2^646264206621 is an apocalyptic number.

It is an amenable number.

646264206621 is a deficient number, since it is larger than the sum of its proper divisors (379899119203).

646264206621 is a wasteful number, since it uses less digits than its factorization.

646264206621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53694 (or 53680 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 45.

The spelling of 646264206621 in words is "six hundred forty-six billion, two hundred sixty-four million, two hundred six thousand, six hundred twenty-one".