668215001779 has 8 divisors (see below), whose sum is σ = 721960186640. Its totient is φ = 614804678496.

The previous prime is 668215001759. The next prime is 668215001789. The reversal of 668215001779 is 977100512866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668215001779 is a prime.

It is a super-2 number, since 2×668215001779² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668215001759) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83711244 + ... + 83719225.

It is an arithmetic number, because the mean of its divisors is an integer number (90245023330).

Almost surely, 2^668215001779 is an apocalyptic number.

668215001779 is a deficient number, since it is larger than the sum of its proper divisors (53745184861).

668215001779 is a wasteful number, since it uses less digits than its factorization.

668215001779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167430789.

The product of its (nonzero) digits is 1270080, while the sum is 52.

The spelling of 668215001779 in words is "six hundred sixty-eight billion, two hundred fifteen million, one thousand, seven hundred seventy-nine".