166402405 has 16 divisors (see below), whose sum is σ = 217995120. Its totient is φ = 121195008.

The previous prime is 166402367. The next prime is 166402421. The reversal of 166402405 is 504204661.

It can be written as a sum of positive squares in 8 ways, for example, as 1896129 + 164506276 = 1377^2 + 12826^2 .

It is a cyclic number.

It is not a de Polignac number, because 166402405 - 2⁷ = 166402277 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, 12790 + ... + 22279.

It is an arithmetic number, because the mean of its divisors is an integer number (13624695).

Almost surely, 2^166402405 is an apocalyptic number.

It is an amenable number.

166402405 is a deficient number, since it is larger than the sum of its proper divisors (51592715).

166402405 is a wasteful number, since it uses less digits than its factorization.

166402405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35160.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 166402405 is about 12899.7056167961. The cubic root of 166402405 is about 550.0301966892.

The spelling of 166402405 in words is "one hundred sixty-six million, four hundred two thousand, four hundred five".