166405427 has 16 divisors (see below), whose sum is σ = 176676864. Its totient is φ = 156492000.

The previous prime is 166405417. The next prime is 166405453. The reversal of 166405427 is 724504661.

It is a cyclic number.

It is not a de Polignac number, because 166405427 - 2¹² = 166401331 is a prime.

It is a super-2 number, since 2×166405427² = 55381532270104658, which contains 22 as substring.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166405417) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 263402 + ... + 264032.

It is an arithmetic number, because the mean of its divisors is an integer number (11042304).

Almost surely, 2^166405427 is an apocalyptic number.

166405427 is a deficient number, since it is larger than the sum of its proper divisors (10271437).

166405427 is a wasteful number, since it uses less digits than its factorization.

166405427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 890.

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 166405427 is about 12899.8227507203. The cubic root of 166405427 is about 550.0335263310.

The spelling of 166405427 in words is "one hundred sixty-six million, four hundred five thousand, four hundred twenty-seven".