668122568438 has 32 divisors (see below), whose sum is σ = 1085197181376. Its totient is φ = 306673164288.

The previous prime is 668122568419. The next prime is 668122568447. The reversal of 668122568438 is 834865221866.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18081470 + ... + 18118382.

It is an arithmetic number, because the mean of its divisors is an integer number (33912411918).

Almost surely, 2^668122568438 is an apocalyptic number.

668122568438 is a deficient number, since it is larger than the sum of its proper divisors (417074612938).

668122568438 is a wasteful number, since it uses less digits than its factorization.

668122568438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40728.

The product of its digits is 26542080, while the sum is 59.

The spelling of 668122568438 in words is "six hundred sixty-eight billion, one hundred twenty-two million, five hundred sixty-eight thousand, four hundred thirty-eight".