21516516552873 has 8 divisors (see below), whose sum is σ = 28705243094208. Its totient is φ = 14336067190064.

The previous prime is 21516516552871. The next prime is 21516516552877. The reversal of 21516516552873 is 37825561561512.

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 21516516552873 - 2¹ = 21516516552871 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21516516552871) 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, 2069288565 + ... + 2069298962.

It is an arithmetic number, because the mean of its divisors is an integer number (3588155386776).

Almost surely, 2^{21516516552873} is an apocalyptic number.

It is an amenable number.

21516516552873 is a deficient number, since it is larger than the sum of its proper divisors (7188726541335).

21516516552873 is a wasteful number, since it uses less digits than its factorization.

21516516552873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4138589263.

The product of its digits is 15120000, while the sum is 57.

The spelling of 21516516552873 in words is "twenty-one trillion, five hundred sixteen billion, five hundred sixteen million, five hundred fifty-two thousand, eight hundred seventy-three".