21252143562 has 16 divisors (see below), whose sum is σ = 45773847840. Its totient is φ = 6539121072.

The previous prime is 21252143537. The next prime is 21252143569. The reversal of 21252143562 is 26534125212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21252143569) 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, 136231612 + ... + 136231767.

It is an arithmetic number, because the mean of its divisors is an integer number (2860865490).

Almost surely, 2^21252143562 is an apocalyptic number.

21252143562 is an abundant number, since it is smaller than the sum of its proper divisors (24521704278).

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

21252143562 is a wasteful number, since it uses less digits than its factorization.

21252143562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272463397.

The product of its digits is 28800, while the sum is 33.

Adding to 21252143562 its reverse (26534125212), we get a palindrome (47786268774).

The spelling of 21252143562 in words is "twenty-one billion, two hundred fifty-two million, one hundred forty-three thousand, five hundred sixty-two".