666402405 has 16 divisors (see below), whose sum is σ = 1066634880. Its totient is φ = 355284288.

The previous prime is 666402383. The next prime is 666402419. The reversal of 666402405 is 504204666.

It is not a de Polignac number, because 666402405 - 2¹⁸ = 666140261 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45531 + ... + 58359.

It is an arithmetic number, because the mean of its divisors is an integer number (66664680).

Almost surely, 2^666402405 is an apocalyptic number.

It is an amenable number.

666402405 is a deficient number, since it is larger than the sum of its proper divisors (400232475).

666402405 is a wasteful number, since it uses less digits than its factorization.

666402405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16300.

The product of its (nonzero) digits is 34560, while the sum is 33.

The square root of 666402405 is about 25814.7710623201. The cubic root of 666402405 is about 873.4650225667.

The spelling of 666402405 in words is "six hundred sixty-six million, four hundred two thousand, four hundred five".