668781867 has 16 divisors (see below), whose sum is σ = 971097120. Its totient is φ = 406931712.

The previous prime is 668781829. The next prime is 668781877. The reversal of 668781867 is 768187866.

It is not a de Polignac number, because 668781867 - 2⁸ = 668781611 is a prime.

It is not an unprimeable number, because it can be changed into a prime (668781877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92868 + ... + 99809.

It is an arithmetic number, because the mean of its divisors is an integer number (60693570).

Almost surely, 2^668781867 is an apocalyptic number.

668781867 is a deficient number, since it is larger than the sum of its proper divisors (302315253).

668781867 is a wasteful number, since it uses less digits than its factorization.

668781867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192782.

The product of its digits is 5419008, while the sum is 57.

The square root of 668781867 is about 25860.8172144656. The cubic root of 668781867 is about 874.5033881845.

The spelling of 668781867 in words is "six hundred sixty-eight million, seven hundred eighty-one thousand, eight hundred sixty-seven".