646622788 has 24 divisors (see below), whose sum is σ = 1308831552. Its totient is φ = 273784224.

The previous prime is 646622749. The next prime is 646622789. The reversal of 646622788 is 887226646.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (646622789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136795 + ... + 141442.

It is an arithmetic number, because the mean of its divisors is an integer number (54534648).

Almost surely, 2^646622788 is an apocalyptic number.

It is an amenable number.

646622788 is an abundant number, since it is smaller than the sum of its proper divisors (662208764).

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

646622788 is a wasteful number, since it uses less digits than its factorization.

646622788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278331 (or 278329 counting only the distinct ones).

The product of its digits is 1548288, while the sum is 49.

The square root of 646622788 is about 25428.7787359126. The cubic root of 646622788 is about 864.7362569232.

The spelling of 646622788 in words is "six hundred forty-six million, six hundred twenty-two thousand, seven hundred eighty-eight".