11124124721 has 4 divisors (see below), whose sum is σ = 11129153652. Its totient is φ = 11119095792.

The previous prime is 11124124681. The next prime is 11124124729. The reversal of 11124124721 is 12742142111.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6502164496 + 4621960225 = 80636^2 + 67985^2 .

It is a cyclic number.

It is not a de Polignac number, because 11124124721 - 2⁶ = 11124124657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11124124729) 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, 2511146 + ... + 2515571.

It is an arithmetic number, because the mean of its divisors is an integer number (2782288413).

Almost surely, 2^11124124721 is an apocalyptic number.

It is an amenable number.

11124124721 is a deficient number, since it is larger than the sum of its proper divisors (5028931).

11124124721 is an equidigital number, since it uses as much as digits as its factorization.

11124124721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5028930.

The product of its digits is 896, while the sum is 26.

Adding to 11124124721 its reverse (12742142111), we get a palindrome (23866266832).

The spelling of 11124124721 in words is "eleven billion, one hundred twenty-four million, one hundred twenty-four thousand, seven hundred twenty-one".