105142121 has 4 divisors (see below), whose sum is σ = 120162432. Its totient is φ = 90121812.

The previous prime is 105142099. The next prime is 105142129. The reversal of 105142121 is 121241501.

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: 121241501 = 17 ⋅7131853.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-105142121 is a prime.

It is a super-2 number, since 2×105142121² = 22109731216757282, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 105142121.

It is not an unprimeable number, because it can be changed into a prime (105142129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7510145 + ... + 7510158.

It is an arithmetic number, because the mean of its divisors is an integer number (30040608).

Almost surely, 2^105142121 is an apocalyptic number.

It is an amenable number.

105142121 is a deficient number, since it is larger than the sum of its proper divisors (15020311).

105142121 is an equidigital number, since it uses as much as digits as its factorization.

105142121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15020310.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 105142121 is about 10253.8832156408. The cubic root of 105142121 is about 471.9821539384.

Adding to 105142121 its reverse (121241501), we get a palindrome (226383622).

The spelling of 105142121 in words is "one hundred five million, one hundred forty-two thousand, one hundred twenty-one".