21121235241 has 16 divisors (see below), whose sum is σ = 28457467968. Its totient is φ = 13933080000.

The previous prime is 21121235227. The next prime is 21121235243. The reversal of 21121235241 is 14253212112.

It is a happy number.

It is not a de Polignac number, because 21121235241 - 2¹⁰ = 21121234217 is a prime.

It is a super-2 number, since 2×21121235241² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121235243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 509391 + ... + 549291.

It is an arithmetic number, because the mean of its divisors is an integer number (1778591748).

Almost surely, 2^21121235241 is an apocalyptic number.

It is an amenable number.

21121235241 is a deficient number, since it is larger than the sum of its proper divisors (7336232727).

21121235241 is a wasteful number, since it uses less digits than its factorization.

21121235241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41752.

The product of its digits is 960, while the sum is 24.

Adding to 21121235241 its reverse (14253212112), we get a palindrome (35374447353).

The spelling of 21121235241 in words is "twenty-one billion, one hundred twenty-one million, two hundred thirty-five thousand, two hundred forty-one".