21326806503 has 12 divisors (see below), whose sum is σ = 30806813128. Its totient is φ = 14217212880.

The previous prime is 21326806499. The next prime is 21326806541. The reversal of 21326806503 is 30560862312.

It is a happy number.

It is not a de Polignac number, because 21326806503 - 2² = 21326806499 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21326806573) 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 11 ways as a sum of consecutive naturals, for example, 226176 + ... + 306282.

Almost surely, 2^21326806503 is an apocalyptic number.

21326806503 is a deficient number, since it is larger than the sum of its proper divisors (9480006625).

21326806503 is a wasteful number, since it uses less digits than its factorization.

21326806503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109694 (or 109691 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 21326806503 in words is "twenty-one billion, three hundred twenty-six million, eight hundred six thousand, five hundred three".