668763365 has 4 divisors (see below), whose sum is σ = 802516044. Its totient is φ = 535010688.

The previous prime is 668763343. The next prime is 668763371. The reversal of 668763365 is 563367866.

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

It can be written as a sum of positive squares in 2 ways, for example, as 70324996 + 598438369 = 8386^2 + 24463^2 .

It is a cyclic number.

It is not a de Polignac number, because 668763365 - 2¹⁸ = 668501221 is a prime.

It is a super-2 number, since 2×668763365² = 894488876732246450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66876332 + ... + 66876341.

It is an arithmetic number, because the mean of its divisors is an integer number (200629011).

Almost surely, 2^668763365 is an apocalyptic number.

It is an amenable number.

668763365 is a deficient number, since it is larger than the sum of its proper divisors (133752679).

668763365 is a wasteful number, since it uses less digits than its factorization.

668763365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133752678.

The product of its digits is 3265920, while the sum is 50.

The square root of 668763365 is about 25860.4594893440. The cubic root of 668763365 is about 874.4953236662.

The spelling of 668763365 in words is "six hundred sixty-eight million, seven hundred sixty-three thousand, three hundred sixty-five".