21221224131 has 8 divisors (see below), whose sum is σ = 28517761024. Its totient is φ = 14036085000.

The previous prime is 21221224081. The next prime is 21221224139. The reversal of 21221224131 is 13142212212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21221224131 - 2⁶ = 21221224067 is a prime.

It is a super-2 number, since 2×21221224131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221224098 and 21221224107.

It is not an unprimeable number, because it can be changed into a prime (21221224139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27848995 + ... + 27849756.

It is an arithmetic number, because the mean of its divisors is an integer number (3564720128).

Almost surely, 2^21221224131 is an apocalyptic number.

21221224131 is a deficient number, since it is larger than the sum of its proper divisors (7296536893).

21221224131 is a wasteful number, since it uses less digits than its factorization.

21221224131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55698881.

The product of its digits is 384, while the sum is 21.

Adding to 21221224131 its reverse (13142212212), we get a palindrome (34363436343).

The spelling of 21221224131 in words is "twenty-one billion, two hundred twenty-one million, two hundred twenty-four thousand, one hundred thirty-one".