646520801 has 4 divisors (see below), whose sum is σ = 647396400. Its totient is φ = 645645204.

The previous prime is 646520789. The next prime is 646520807. The reversal of 646520801 is 108025646.

646520801 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 646520801 - 2⁶ = 646520737 is a prime.

It is a super-2 number, since 2×646520801² = 835978292251363202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646520807) 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, 436691 + ... + 438168.

It is an arithmetic number, because the mean of its divisors is an integer number (161849100).

Almost surely, 2^646520801 is an apocalyptic number.

It is an amenable number.

646520801 is a deficient number, since it is larger than the sum of its proper divisors (875599).

646520801 is an equidigital number, since it uses as much as digits as its factorization.

646520801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875598.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 646520801 is about 25426.7733108234. The cubic root of 646520801 is about 864.6907917281.

The spelling of 646520801 in words is "six hundred forty-six million, five hundred twenty thousand, eight hundred one".