21242354252 has 24 divisors (see below), whose sum is σ = 42590677920. Its totient is φ = 9081158400.

The previous prime is 21242354251. The next prime is 21242354269. The reversal of 21242354252 is 25245324212.

It is a super-2 number, since 2×21242354252² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21242354251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 934727 + ... + 957182.

It is an arithmetic number, because the mean of its divisors is an integer number (1774611580).

Almost surely, 2^21242354252 is an apocalyptic number.

It is an amenable number.

21242354252 is an abundant number, since it is smaller than the sum of its proper divisors (21348323668).

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

21242354252 is a wasteful number, since it uses less digits than its factorization.

21242354252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1892321 (or 1892319 counting only the distinct ones).

The product of its digits is 38400, while the sum is 32.

Adding to 21242354252 its reverse (25245324212), we get a palindrome (46487678464).

The spelling of 21242354252 in words is "twenty-one billion, two hundred forty-two million, three hundred fifty-four thousand, two hundred fifty-two".