21140893439 has 4 divisors (see below), whose sum is σ = 22384475424. Its totient is φ = 19897311456.

The previous prime is 21140893429. The next prime is 21140893447. The reversal of 21140893439 is 93439804112.

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

It is a cyclic number.

It is not a de Polignac number, because 21140893439 - 2⁸ = 21140893183 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21140893439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21140893429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 621790967 + ... + 621791000.

It is an arithmetic number, because the mean of its divisors is an integer number (5596118856).

Almost surely, 2^21140893439 is an apocalyptic number.

21140893439 is a deficient number, since it is larger than the sum of its proper divisors (1243581985).

21140893439 is a wasteful number, since it uses less digits than its factorization.

21140893439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1243581984.

The product of its (nonzero) digits is 186624, while the sum is 44.

The spelling of 21140893439 in words is "twenty-one billion, one hundred forty million, eight hundred ninety-three thousand, four hundred thirty-nine".