405166376221 has 2 divisors, whose sum is σ = 405166376222. Its totient is φ = 405166376220.

The previous prime is 405166376213. The next prime is 405166376227. The reversal of 405166376221 is 122673661504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 320371848196 + 84794528025 = 566014^2 + 291195^2 .

It is a cyclic number.

It is not a de Polignac number, because 405166376221 - 2³ = 405166376213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405166376227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202583188110 + 202583188111.

It is an arithmetic number, because the mean of its divisors is an integer number (202583188111).

Almost surely, 2^405166376221 is an apocalyptic number.

It is an amenable number.

405166376221 is a deficient number, since it is larger than the sum of its proper divisors (1).

405166376221 is an equidigital number, since it uses as much as digits as its factorization.

405166376221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 43.

The spelling of 405166376221 in words is "four hundred five billion, one hundred sixty-six million, three hundred seventy-six thousand, two hundred twenty-one".