105612121 has 4 divisors (see below), whose sum is σ = 106013952. Its totient is φ = 105210292.

The previous prime is 105612083. The next prime is 105612139. The reversal of 105612121 is 121216501.

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: 121216501 = 7 ⋅17316643.

It is a cyclic number.

It is not a de Polignac number, because 105612121 - 2⁹ = 105611609 is a prime.

It is a super-2 number, since 2×105612121² = 22307840204237282, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (105612151) 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, 200521 + ... + 201046.

It is an arithmetic number, because the mean of its divisors is an integer number (26503488).

Almost surely, 2^105612121 is an apocalyptic number.

It is an amenable number.

105612121 is a deficient number, since it is larger than the sum of its proper divisors (401831).

105612121 is an equidigital number, since it uses as much as digits as its factorization.

105612121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401830.

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 105612121 is about 10276.7758076159. The cubic root of 105612121 is about 472.6843840539.

Adding to 105612121 its reverse (121216501), we get a palindrome (226828622).

The spelling of 105612121 in words is "one hundred five million, six hundred twelve thousand, one hundred twenty-one".