21739948559 has 16 divisors (see below), whose sum is σ = 25380676608. Its totient is φ = 18233176032.

The previous prime is 21739948547. The next prime is 21739948583. The reversal of 21739948559 is 95584993712.

It is a cyclic number.

It is not a de Polignac number, because 21739948559 - 2³² = 17444981263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21739948859) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2148917 + ... + 2159009.

It is an arithmetic number, because the mean of its divisors is an integer number (1586292288).

Almost surely, 2^21739948559 is an apocalyptic number.

21739948559 is a deficient number, since it is larger than the sum of its proper divisors (3640728049).

21739948559 is a wasteful number, since it uses less digits than its factorization.

21739948559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16694.

The product of its digits is 24494400, while the sum is 62.

The spelling of 21739948559 in words is "twenty-one billion, seven hundred thirty-nine million, nine hundred forty-eight thousand, five hundred fifty-nine".