21539874629 has 16 divisors (see below), whose sum is σ = 26520426240. Its totient is φ = 17036231040.

The previous prime is 21539874557. The next prime is 21539874649. The reversal of 21539874629 is 92647893512.

It is a cyclic number.

It is not a de Polignac number, because 21539874629 - 2¹² = 21539870533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21539874649) 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, 211577 + ... + 296385.

It is an arithmetic number, because the mean of its divisors is an integer number (1657526640).

Almost surely, 2^21539874629 is an apocalyptic number.

It is an amenable number.

21539874629 is a deficient number, since it is larger than the sum of its proper divisors (4980551611).

21539874629 is a wasteful number, since it uses less digits than its factorization.

21539874629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87620.

The product of its digits is 6531840, while the sum is 56.

The spelling of 21539874629 in words is "twenty-one billion, five hundred thirty-nine million, eight hundred seventy-four thousand, six hundred twenty-nine".