166252121 has 4 divisors (see below), whose sum is σ = 190002432. Its totient is φ = 142501812.

The previous prime is 166252117. The next prime is 166252153. The reversal of 166252121 is 121252661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 121252661 = 19 ⋅6381719.

It is a cyclic number.

It is not a de Polignac number, because 166252121 - 2² = 166252117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166252421) 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, 11875145 + ... + 11875158.

It is an arithmetic number, because the mean of its divisors is an integer number (47500608).

Almost surely, 2^166252121 is an apocalyptic number.

It is an amenable number.

166252121 is a deficient number, since it is larger than the sum of its proper divisors (23750311).

166252121 is an equidigital number, since it uses as much as digits as its factorization.

166252121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23750310.

The product of its digits is 1440, while the sum is 26.

The square root of 166252121 is about 12893.8792068175. The cubic root of 166252121 is about 549.8645627946.

The spelling of 166252121 in words is "one hundred sixty-six million, two hundred fifty-two thousand, one hundred twenty-one".