166398945 has 16 divisors (see below), whose sum is σ = 267416640. Its totient is φ = 88353344.

The previous prime is 166398943. The next prime is 166398971. The reversal of 166398945 is 549893661.

It is a cyclic number.

It is not a de Polignac number, because 166398945 - 2¹ = 166398943 is a prime.

It is a super-2 number, since 2×166398945² = 55377217794226050, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166398943) 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, 21030 + ... + 27839.

It is an arithmetic number, because the mean of its divisors is an integer number (16713540).

Almost surely, 2^166398945 is an apocalyptic number.

166398945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166398945 is a deficient number, since it is larger than the sum of its proper divisors (101017695).

166398945 is a wasteful number, since it uses less digits than its factorization.

166398945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49104.

The product of its digits is 1399680, while the sum is 51.

The square root of 166398945 is about 12899.5715045113. The cubic root of 166398945 is about 550.0263844092.

The spelling of 166398945 in words is "one hundred sixty-six million, three hundred ninety-eight thousand, nine hundred forty-five".