666767437667 has 4 divisors (see below), whose sum is σ = 676719190536. Its totient is φ = 656815684800.

The previous prime is 666767437579. The next prime is 666767437691. The reversal of 666767437667 is 766734767666.

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

It is a cyclic number.

It is not a de Polignac number, because 666767437667 - 2¹⁸ = 666767175523 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666767437667.

It is not an unprimeable number, because it can be changed into a prime (666767437267) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4975876334 + ... + 4975876467.

It is an arithmetic number, because the mean of its divisors is an integer number (169179797634).

Almost surely, 2^666767437667 is an apocalyptic number.

666767437667 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

666767437667 is a deficient number, since it is larger than the sum of its proper divisors (9951752869).

666767437667 is an equidigital number, since it uses as much as digits as its factorization.

666767437667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9951752868.

The product of its digits is 1344252672, while the sum is 71.

The spelling of 666767437667 in words is "six hundred sixty-six billion, seven hundred sixty-seven million, four hundred thirty-seven thousand, six hundred sixty-seven".