21250022243 has 4 divisors (see below), whose sum is σ = 21250328400. Its totient is φ = 21249716088.

The previous prime is 21250022239. The next prime is 21250022249. The reversal of 21250022243 is 34222005212.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21250022243 - 2² = 21250022239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21250022249) 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 3 ways as a sum of consecutive naturals, for example, 6458 + ... + 206256.

It is an arithmetic number, because the mean of its divisors is an integer number (5312582100).

Almost surely, 2^21250022243 is an apocalyptic number.

21250022243 is a deficient number, since it is larger than the sum of its proper divisors (306157).

21250022243 is a wasteful number, since it uses less digits than its factorization.

21250022243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306156.

The product of its (nonzero) digits is 1920, while the sum is 23.

Adding to 21250022243 its reverse (34222005212), we get a palindrome (55472027455).

The spelling of 21250022243 in words is "twenty-one billion, two hundred fifty million, twenty-two thousand, two hundred forty-three".