646551909742 has 16 divisors (see below), whose sum is σ = 972009424512. Its totient is φ = 322549427200.

The previous prime is 646551909733. The next prime is 646551909749. The reversal of 646551909742 is 247909155646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646551909749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1812003 + ... + 2139265.

It is an arithmetic number, because the mean of its divisors is an integer number (60750589032).

Almost surely, 2^646551909742 is an apocalyptic number.

646551909742 is a deficient number, since it is larger than the sum of its proper divisors (325457514770).

646551909742 is a wasteful number, since it uses less digits than its factorization.

646551909742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329483.

The product of its (nonzero) digits is 16329600, while the sum is 58.

The spelling of 646551909742 in words is "six hundred forty-six billion, five hundred fifty-one million, nine hundred nine thousand, seven hundred forty-two".