668219629654 has 4 divisors (see below), whose sum is σ = 1002329444484. Its totient is φ = 334109814826.

The previous prime is 668219629607. The next prime is 668219629681. The reversal of 668219629654 is 456926912866.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167054907412 + ... + 167054907415.

It is an arithmetic number, because the mean of its divisors is an integer number (250582361121).

Almost surely, 2^668219629654 is an apocalyptic number.

668219629654 is a deficient number, since it is larger than the sum of its proper divisors (334109814830).

668219629654 is a wasteful number, since it uses less digits than its factorization.

668219629654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334109814829.

The product of its digits is 67184640, while the sum is 64.

The spelling of 668219629654 in words is "six hundred sixty-eight billion, two hundred nineteen million, six hundred twenty-nine thousand, six hundred fifty-four".