405666799 has 2 divisors, whose sum is σ = 405666800. Its totient is φ = 405666798.

The previous prime is 405666797. The next prime is 405666827. The reversal of 405666799 is 997666504.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 405666799 - 2¹ = 405666797 is a prime.

Together with 405666797, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405666791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202833399 + 202833400.

It is an arithmetic number, because the mean of its divisors is an integer number (202833400).

Almost surely, 2^405666799 is an apocalyptic number.

405666799 is a deficient number, since it is larger than the sum of its proper divisors (1).

405666799 is an equidigital number, since it uses as much as digits as its factorization.

405666799 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2449440, while the sum is 52.

The square root of 405666799 is about 20141.1717385062. The cubic root of 405666799 is about 740.2694410834.

The spelling of 405666799 in words is "four hundred five million, six hundred sixty-six thousand, seven hundred ninety-nine".