21250013254 has 4 divisors (see below), whose sum is σ = 31875019884. Its totient is φ = 10625006626.

The previous prime is 21250013249. The next prime is 21250013261. The reversal of 21250013254 is 45231005212.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5312503312 + ... + 5312503315.

It is an arithmetic number, because the mean of its divisors is an integer number (7968754971).

Almost surely, 2^21250013254 is an apocalyptic number.

21250013254 is a deficient number, since it is larger than the sum of its proper divisors (10625006630).

21250013254 is a wasteful number, since it uses less digits than its factorization.

21250013254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10625006629.

The product of its (nonzero) digits is 2400, while the sum is 25.

Adding to 21250013254 its reverse (45231005212), we get a palindrome (66481018466).

The spelling of 21250013254 in words is "twenty-one billion, two hundred fifty million, thirteen thousand, two hundred fifty-four".