21222111725 has 24 divisors (see below), whose sum is σ = 26529332520. Its totient is φ = 16839889920.

The previous prime is 21222111709. The next prime is 21222111761. The reversal of 21222111725 is 52711122212.

It can be written as a sum of positive squares in 12 ways, for example, as 5713394569 + 15508717156 = 75587^2 + 124534^2 .

It is not a de Polignac number, because 21222111725 - 2⁴ = 21222111709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222111694 and 21222111703.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6824471 + ... + 6827579.

It is an arithmetic number, because the mean of its divisors is an integer number (1105388855).

Almost surely, 2^21222111725 is an apocalyptic number.

21222111725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21222111725 is a deficient number, since it is larger than the sum of its proper divisors (5307220795).

21222111725 is a wasteful number, since it uses less digits than its factorization.

21222111725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5249 (or 5244 counting only the distinct ones).

The product of its digits is 1120, while the sum is 26.

Adding to 21222111725 its reverse (52711122212), we get a palindrome (73933233937).

The spelling of 21222111725 in words is "twenty-one billion, two hundred twenty-two million, one hundred eleven thousand, seven hundred twenty-five".