21144531250 has 40 divisors (see below), whose sum is σ = 39653316252. Its totient is φ = 8456250000.

The previous prime is 21144531227. The next prime is 21144531253. The reversal of 21144531250 is 5213544112.

It can be written as a sum of positive squares in 10 ways, for example, as 10504815049 + 10639716201 = 102493^2 + 103149^2 .

It is not an unprimeable number, because it can be changed into a prime (21144531253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3903544 + ... + 3908956.

Almost surely, 2^21144531250 is an apocalyptic number.

21144531250 is a deficient number, since it is larger than the sum of its proper divisors (18508785002).

21144531250 is an frugal number, since it uses more digits than its factorization.

21144531250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5460 (or 5420 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The spelling of 21144531250 in words is "twenty-one billion, one hundred forty-four million, five hundred thirty-one thousand, two hundred fifty".