105243921 has 16 divisors (see below), whose sum is σ = 156520320. Its totient is φ = 69891120.

The previous prime is 105243913. The next prime is 105243937. The reversal of 105243921 is 129342501.

It is not a de Polignac number, because 105243921 - 2³ = 105243913 is a prime.

It is a super-2 number, since 2×105243921² = 22152565814908482, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (105243911) 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, 310 + ... + 14511.

It is an arithmetic number, because the mean of its divisors is an integer number (9782520).

Almost surely, 2^105243921 is an apocalyptic number.

It is an amenable number.

105243921 is a deficient number, since it is larger than the sum of its proper divisors (51276399).

105243921 is a wasteful number, since it uses less digits than its factorization.

105243921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15093 (or 15087 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 105243921 is about 10258.8459877318. The cubic root of 105243921 is about 472.1344312697.

The spelling of 105243921 in words is "one hundred five million, two hundred forty-three thousand, nine hundred twenty-one".