21225025124 has 12 divisors (see below), whose sum is σ = 37526720364. Its totient is φ = 10503105024.

The previous prime is 21225024967. The next prime is 21225025139. The reversal of 21225025124 is 42152052212.

It can be written as a sum of positive squares in 2 ways, for example, as 7554738724 + 13670286400 = 86918^2 + 116920^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21225025093 and 21225025102.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27351449 + ... + 27352224.

It is an arithmetic number, because the mean of its divisors is an integer number (3127226697).

Almost surely, 2^21225025124 is an apocalyptic number.

It is an amenable number.

21225025124 is a deficient number, since it is larger than the sum of its proper divisors (16301695240).

21225025124 is a wasteful number, since it uses less digits than its factorization.

21225025124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54703774 (or 54703772 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 26.

Adding to 21225025124 its reverse (42152052212), we get a palindrome (63377077336).

The spelling of 21225025124 in words is "twenty-one billion, two hundred twenty-five million, twenty-five thousand, one hundred twenty-four".