166020642 has 18 divisors (see below), whose sum is σ = 359829873. Its totient is φ = 55321992.

The previous prime is 166020619. The next prime is 166020643. The reversal of 166020642 is 246020661.

It is a happy number.

166020642 is a `hidden beast` number, since 16 + 6 + 0 + 2 + 0 + 642 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 142778601 + 23242041 = 11949^2 + 4821^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=9111.

It is not an unprimeable number, because it can be changed into a prime (166020643) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 53148 + ... + 56184.

Almost surely, 2^166020642 is an apocalyptic number.

166020642 is an abundant number, since it is smaller than the sum of its proper divisors (193809231).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166020642 is an frugal number, since it uses more digits than its factorization.

166020642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6082 (or 3042 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 166020642 is about 12884.8997667813. The cubic root of 166020642 is about 549.6092453140.

The spelling of 166020642 in words is "one hundred sixty-six million, twenty thousand, six hundred forty-two".