668920749870 has 24 divisors (see below), whose sum is σ = 1605420551016. Its totient is φ = 178377672048.

The previous prime is 668920749829. The next prime is 668920749877. The reversal of 668920749870 is 78947029866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668920749877) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4405029 + ... + 4554351.

It is an arithmetic number, because the mean of its divisors is an integer number (66892522959).

Almost surely, 2^668920749870 is an apocalyptic number.

668920749870 is an abundant number, since it is smaller than the sum of its proper divisors (936499801146).

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

668920749870 is an frugal number, since it uses more digits than its factorization.

668920749870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298656 (or 149333 counting only the distinct ones).

The product of its (nonzero) digits is 73156608, while the sum is 66.

The spelling of 668920749870 in words is "six hundred sixty-eight billion, nine hundred twenty million, seven hundred forty-nine thousand, eight hundred seventy".