646663769910 has 48 divisors (see below), whose sum is σ = 1735562125440. Its totient is φ = 166880972160.

The previous prime is 646663769893. The next prime is 646663770007. The reversal of 646663769910 is 19967366646.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 115886775 + ... + 115892354.

It is an arithmetic number, because the mean of its divisors is an integer number (36157544280).

Almost surely, 2^646663769910 is an apocalyptic number.

646663769910 is an abundant number, since it is smaller than the sum of its proper divisors (1088898355530).

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

646663769910 is a wasteful number, since it uses less digits than its factorization.

646663769910 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231779173 (or 231779170 counting only the distinct ones).

The product of its (nonzero) digits is 52907904, while the sum is 63.

The spelling of 646663769910 in words is "six hundred forty-six billion, six hundred sixty-three million, seven hundred sixty-nine thousand, nine hundred ten".