21545143144 has 32 divisors (see below), whose sum is σ = 46191568320. Its totient is φ = 9228951936.

The previous prime is 21545143129. The next prime is 21545143153. The reversal of 21545143144 is 44134154512.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15087 + ... + 208129.

It is an arithmetic number, because the mean of its divisors is an integer number (1443486510).

Almost surely, 2^21545143144 is an apocalyptic number.

It is an amenable number.

21545143144 is an abundant number, since it is smaller than the sum of its proper divisors (24646425176).

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

21545143144 is a wasteful number, since it uses less digits than its factorization.

21545143144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195049 (or 195045 counting only the distinct ones).

The product of its digits is 38400, while the sum is 34.

Adding to 21545143144 its reverse (44134154512), we get a palindrome (65679297656).

The spelling of 21545143144 in words is "twenty-one billion, five hundred forty-five million, one hundred forty-three thousand, one hundred forty-four".