166507489 has 4 divisors (see below), whose sum is σ = 168156180. Its totient is φ = 164858800.

The previous prime is 166507487. The next prime is 166507577. The reversal of 166507489 is 984705661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 984705661 = 101 ⋅9749561.

It can be written as a sum of positive squares in 2 ways, for example, as 163328400 + 3179089 = 12780^2 + 1783^2 .

It is a cyclic number.

It is not a de Polignac number, because 166507489 - 2¹ = 166507487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166507487) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 824194 + ... + 824395.

It is an arithmetic number, because the mean of its divisors is an integer number (42039045).

Almost surely, 2^166507489 is an apocalyptic number.

It is an amenable number.

166507489 is a deficient number, since it is larger than the sum of its proper divisors (1648691).

166507489 is a wasteful number, since it uses less digits than its factorization.

166507489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1648690.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 166507489 is about 12903.7780901564. The cubic root of 166507489 is about 550.1459546527.

The spelling of 166507489 in words is "one hundred sixty-six million, five hundred seven thousand, four hundred eighty-nine".