166252543121 has 16 divisors (see below), whose sum is σ = 190822754304. Its totient is φ = 141888623184.

The previous prime is 166252543117. The next prime is 166252543123. The reversal of 166252543121 is 121345252661.

It is not a de Polignac number, because 166252543121 - 2² = 166252543117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166252543123) 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, 1458626 + ... + 1568468.

It is an arithmetic number, because the mean of its divisors is an integer number (11926422144).

Almost surely, 2^166252543121 is an apocalyptic number.

It is an amenable number.

166252543121 is a deficient number, since it is larger than the sum of its proper divisors (24570211183).

166252543121 is a wasteful number, since it uses less digits than its factorization.

166252543121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110780.

The product of its digits is 86400, while the sum is 38.

Adding to 166252543121 its reverse (121345252661), we get a palindrome (287597795782).

The spelling of 166252543121 in words is "one hundred sixty-six billion, two hundred fifty-two million, five hundred forty-three thousand, one hundred twenty-one".