21225312634 has 8 divisors (see below), whose sum is σ = 33710790708. Its totient is φ = 9988382400.

The previous prime is 21225312631. The next prime is 21225312679. The reversal of 21225312634 is 43621352212.

It can be written as a sum of positive squares in 2 ways, for example, as 18740788609 + 2484524025 = 136897^2 + 49845^2 .

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

It is a super-2 number, since 2×21225312634² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21225312596 and 21225312605.

It is not an unprimeable number, because it can be changed into a prime (21225312631) 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, 312136917 + ... + 312136984.

Almost surely, 2^21225312634 is an apocalyptic number.

21225312634 is a deficient number, since it is larger than the sum of its proper divisors (12485478074).

21225312634 is a wasteful number, since it uses less digits than its factorization.

21225312634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624273920.

The product of its digits is 17280, while the sum is 31.

Adding to 21225312634 its reverse (43621352212), we get a palindrome (64846664846).

The spelling of 21225312634 in words is "twenty-one billion, two hundred twenty-five million, three hundred twelve thousand, six hundred thirty-four".