667755656152221 has 96 divisors (see below), whose sum is σ = 1112786213591808. Its totient is φ = 348719113267200.

The previous prime is 667755656152147. The next prime is 667755656152261. The reversal of 667755656152221 is 122251656557766.

It is a happy number.

It is not a de Polignac number, because 667755656152221 - 2¹⁰ = 667755656151197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667755656152261) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 13584117175 + ... + 13584166331.

It is an arithmetic number, because the mean of its divisors is an integer number (11591523058248).

Almost surely, 2^{667755656152221} is an apocalyptic number.

It is an amenable number.

667755656152221 is a deficient number, since it is larger than the sum of its proper divisors (445030557439587).

667755656152221 is a wasteful number, since it uses less digits than its factorization.

667755656152221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87191 (or 87178 counting only the distinct ones).

The product of its digits is 317520000, while the sum is 66.

The spelling of 667755656152221 in words is "six hundred sixty-seven trillion, seven hundred fifty-five billion, six hundred fifty-six million, one hundred fifty-two thousand, two hundred twenty-one".