21587857873 has 8 divisors (see below), whose sum is σ = 21720928320. Its totient is φ = 21454939440.

The previous prime is 21587857871. The next prime is 21587857919. The reversal of 21587857873 is 37875878512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21587857873 - 2¹ = 21587857871 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21587857871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 253758 + ... + 327976.

It is an arithmetic number, because the mean of its divisors is an integer number (2715116040).

Almost surely, 2^21587857873 is an apocalyptic number.

It is an amenable number.

21587857873 is a deficient number, since it is larger than the sum of its proper divisors (133070447).

21587857873 is a wasteful number, since it uses less digits than its factorization.

21587857873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76007.

The product of its digits is 26342400, while the sum is 61.

The spelling of 21587857873 in words is "twenty-one billion, five hundred eighty-seven million, eight hundred fifty-seven thousand, eight hundred seventy-three".