166661361 has 32 divisors (see below), whose sum is σ = 252470400. Its totient is φ = 108630720.

The previous prime is 166661359. The next prime is 166661393. The reversal of 166661361 is 163166661.

It is a happy number.

It is not a de Polignac number, because 166661361 - 2¹ = 166661359 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166661321) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 327175 + ... + 327683.

It is an arithmetic number, because the mean of its divisors is an integer number (7889700).

Almost surely, 2^166661361 is an apocalyptic number.

It is an amenable number.

166661361 is a deficient number, since it is larger than the sum of its proper divisors (85809039).

166661361 is a wasteful number, since it uses less digits than its factorization.

166661361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 766 (or 760 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 166661361 is about 12909.7389981363. The cubic root of 166661361 is about 550.3153684454.

The spelling of 166661361 in words is "one hundred sixty-six million, six hundred sixty-one thousand, three hundred sixty-one".