21243032252 has 24 divisors (see below), whose sum is σ = 40431340992. Its totient is φ = 9707400000.

The previous prime is 21243032249. The next prime is 21243032273. The reversal of 21243032252 is 25223034212.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2017124 + ... + 2027627.

It is an arithmetic number, because the mean of its divisors is an integer number (1684639208).

Almost surely, 2^21243032252 is an apocalyptic number.

It is an amenable number.

21243032252 is a deficient number, since it is larger than the sum of its proper divisors (19188308740).

21243032252 is a wasteful number, since it uses less digits than its factorization.

21243032252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4044869 (or 4044867 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 26.

Adding to 21243032252 its reverse (25223034212), we get a palindrome (46466066464).

The spelling of 21243032252 in words is "twenty-one billion, two hundred forty-three million, thirty-two thousand, two hundred fifty-two".