21386754250 has 16 divisors (see below), whose sum is σ = 40036004424. Its totient is φ = 8554701600.

The previous prime is 21386754247. The next prime is 21386754251. The reversal of 21386754250 is 5245768312.

It can be written as a sum of positive squares in 4 ways, for example, as 13780646881 + 7606107369 = 117391^2 + 87213^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21386754197 and 21386754206.

It is not an unprimeable number, because it can be changed into a prime (21386754251) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 42773259 + ... + 42773758.

Almost surely, 2^21386754250 is an apocalyptic number.

21386754250 is a deficient number, since it is larger than the sum of its proper divisors (18649250174).

21386754250 is an equidigital number, since it uses as much as digits as its factorization.

21386754250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85547034 (or 85547024 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 43.

The spelling of 21386754250 in words is "twenty-one billion, three hundred eighty-six million, seven hundred fifty-four thousand, two hundred fifty".