21144503252 has 12 divisors (see below), whose sum is σ = 37022297760. Its totient is φ = 10566703896.

The previous prime is 21144503239. The next prime is 21144503279. The reversal of 21144503252 is 25230544112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1378352 + ... + 1393607.

It is an arithmetic number, because the mean of its divisors is an integer number (3085191480).

Almost surely, 2^21144503252 is an apocalyptic number.

It is an amenable number.

21144503252 is a deficient number, since it is larger than the sum of its proper divisors (15877794508).

21144503252 is a wasteful number, since it uses less digits than its factorization.

21144503252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2773870 (or 2773868 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 29.

The spelling of 21144503252 in words is "twenty-one billion, one hundred forty-four million, five hundred three thousand, two hundred fifty-two".