21245441552 has 20 divisors (see below), whose sum is σ = 43584399036. Its totient is φ = 9997854720.

The previous prime is 21245441531. The next prime is 21245441561. The reversal of 21245441552 is 25514454212.

It can be written as a sum of positive squares in 2 ways, for example, as 15739207936 + 5506233616 = 125456^2 + 74204^2 .

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, 39053849 + ... + 39054392.

Almost surely, 2^21245441552 is an apocalyptic number.

It is an amenable number.

21245441552 is an abundant number, since it is smaller than the sum of its proper divisors (22338957484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21245441552 is a wasteful number, since it uses less digits than its factorization.

21245441552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78108266 (or 78108260 counting only the distinct ones).

The product of its digits is 64000, while the sum is 35.

Adding to 21245441552 its reverse (25514454212), we get a palindrome (46759895764).

The spelling of 21245441552 in words is "twenty-one billion, two hundred forty-five million, four hundred forty-one thousand, five hundred fifty-two".