21054144250 has 32 divisors (see below), whose sum is σ = 39426658128. Its totient is φ = 8418816000.

The previous prime is 21054144203. The next prime is 21054144263. The reversal of 21054144250 is 5244145012.

It can be written as a sum of positive squares in 8 ways, for example, as 577392841 + 20476751409 = 24029^2 + 143097^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 827722 + ... + 852778.

Almost surely, 2^21054144250 is an apocalyptic number.

21054144250 is a deficient number, since it is larger than the sum of its proper divisors (18372513878).

21054144250 is a wasteful number, since it uses less digits than its factorization.

21054144250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28435 (or 28425 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 28.

Adding to 21054144250 its reverse (5244145012), we get a palindrome (26298289262).

The spelling of 21054144250 in words is "twenty-one billion, fifty-four million, one hundred forty-four thousand, two hundred fifty".