21516085393 has 8 divisors (see below), whose sum is σ = 24707466720. Its totient is φ = 18530599680.

The previous prime is 21516085387. The next prime is 21516085403. The reversal of 21516085393 is 39358061512.

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

It is not a de Polignac number, because 21516085393 - 2¹⁷ = 21515954321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21516185393) 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, 51473680 + ... + 51474097.

It is an arithmetic number, because the mean of its divisors is an integer number (3088433340).

Almost surely, 2^21516085393 is an apocalyptic number.

It is an amenable number.

21516085393 is a deficient number, since it is larger than the sum of its proper divisors (3191381327).

21516085393 is a wasteful number, since it uses less digits than its factorization.

21516085393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102947807.

The product of its (nonzero) digits is 194400, while the sum is 43.

The spelling of 21516085393 in words is "twenty-one billion, five hundred sixteen million, eighty-five thousand, three hundred ninety-three".