667407474221 has 2 divisors, whose sum is σ = 667407474222. Its totient is φ = 667407474220.

The previous prime is 667407474163. The next prime is 667407474263. The reversal of 667407474221 is 122474704766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 590615305225 + 76792168996 = 768515^2 + 277114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667407474221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 667407474221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667467474221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333703737110 + 333703737111.

It is an arithmetic number, because the mean of its divisors is an integer number (333703737111).

Almost surely, 2^667407474221 is an apocalyptic number.

It is an amenable number.

667407474221 is a deficient number, since it is larger than the sum of its proper divisors (1).

667407474221 is an equidigital number, since it uses as much as digits as its factorization.

667407474221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3161088, while the sum is 50.

The spelling of 667407474221 in words is "six hundred sixty-seven billion, four hundred seven million, four hundred seventy-four thousand, two hundred twenty-one".