166197538 has 16 divisors (see below), whose sum is σ = 268797816. Its totient is φ = 76613760.

The previous prime is 166197523. The next prime is 166197557. The reversal of 166197538 is 835791661.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 87928129 + 78269409 = 9377^2 + 8847^2 .

It is a super-2 number, since 2×166197538² = 55243243274522888, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21070 + ... + 27862.

Almost surely, 2^166197538 is an apocalyptic number.

166197538 is a deficient number, since it is larger than the sum of its proper divisors (102600278).

166197538 is a wasteful number, since it uses less digits than its factorization.

166197538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7749.

The product of its digits is 272160, while the sum is 46.

The square root of 166197538 is about 12891.7624086081. The cubic root of 166197538 is about 549.8043800183.

It can be divided in two parts, 1661 and 97538, that added together give a palindrome (99199).

The spelling of 166197538 in words is "one hundred sixty-six million, one hundred ninety-seven thousand, five hundred thirty-eight".