166201605 has 64 divisors (see below), whose sum is σ = 315705600. Its totient is φ = 82667520.

The previous prime is 166201597. The next prime is 166201627. The reversal of 166201605 is 506102661.

It is a happy number.

It is not a de Polignac number, because 166201605 - 2³ = 166201597 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 318745 + ... + 319265.

It is an arithmetic number, because the mean of its divisors is an integer number (4932900).

Almost surely, 2^166201605 is an apocalyptic number.

166201605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166201605 is a deficient number, since it is larger than the sum of its proper divisors (149503995).

166201605 is a wasteful number, since it uses less digits than its factorization.

166201605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691 (or 685 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 166201605 is about 12891.9201440282. The cubic root of 166201605 is about 549.8088647141.

It can be divided in two parts, 16620 and 1605, that added together give a square (18225 = 135²).

The spelling of 166201605 in words is "one hundred sixty-six million, two hundred one thousand, six hundred five".