642767663779 has 18 divisors (see below), whose sum is σ = 680835804180. Its totient is φ = 605147010048.

The previous prime is 642767663711. The next prime is 642767663801. The reversal of 642767663779 is 977366767246.

642767663779 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 642767663779 - 2²⁹ = 642230792867 is a prime.

It is a Smith number, since the sum of its digits (70) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642767663579) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 674467167 + ... + 674468119.

Almost surely, 2^642767663779 is an apocalyptic number.

642767663779 is a deficient number, since it is larger than the sum of its proper divisors (38068140401).

642767663779 is an frugal number, since it uses more digits than its factorization.

642767663779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2311 (or 1165 counting only the distinct ones).

The product of its digits is 672126336, while the sum is 70.

The spelling of 642767663779 in words is "six hundred forty-two billion, seven hundred sixty-seven million, six hundred sixty-three thousand, seven hundred seventy-nine".