646415777020 has 24 divisors (see below), whose sum is σ = 1461894142464. Its totient is φ = 238676594496.

The previous prime is 646415776991. The next prime is 646415777023. The reversal of 646415777020 is 20777514646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646415777023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1243107004 + ... + 1243107523.

It is an arithmetic number, because the mean of its divisors is an integer number (60912255936).

Almost surely, 2^646415777020 is an apocalyptic number.

It is an amenable number.

646415777020 is an abundant number, since it is smaller than the sum of its proper divisors (815478365444).

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

646415777020 is a wasteful number, since it uses less digits than its factorization.

646415777020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2486214549 (or 2486214547 counting only the distinct ones).

The product of its (nonzero) digits is 1975680, while the sum is 49.

The spelling of 646415777020 in words is "six hundred forty-six billion, four hundred fifteen million, seven hundred seventy-seven thousand, twenty".