21455130252 has 48 divisors (see below), whose sum is σ = 50615736192. Its totient is φ = 7072828800.

The previous prime is 21455130241. The next prime is 21455130329. The reversal of 21455130252 is 25203155412.

It is a super-2 number, since 2×21455130252² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 757783 + ... + 785585.

It is an arithmetic number, because the mean of its divisors is an integer number (1054494504).

Almost surely, 2^21455130252 is an apocalyptic number.

It is an amenable number.

21455130252 is an abundant number, since it is smaller than the sum of its proper divisors (29160605940).

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

21455130252 is a wasteful number, since it uses less digits than its factorization.

21455130252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28518 (or 28516 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 21455130252 its reverse (25203155412), we get a palindrome (46658285664).

The spelling of 21455130252 in words is "twenty-one billion, four hundred fifty-five million, one hundred thirty thousand, two hundred fifty-two".