21115673765563 has 32 divisors (see below), whose sum is σ = 23214294714240. Its totient is φ = 19088780820480.

The previous prime is 21115673765519. The next prime is 21115673765603. The reversal of 21115673765563 is 36556737651112.

It is a cyclic number.

It is not a de Polignac number, because 21115673765563 - 2¹³ = 21115673757371 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21115673765498 and 21115673765507.

It is not an unprimeable number, because it can be changed into a prime (21115673765503) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 119799483 + ... + 119975611.

It is an arithmetic number, because the mean of its divisors is an integer number (725446709820).

Almost surely, 2^{21115673765563} is an apocalyptic number.

21115673765563 is a deficient number, since it is larger than the sum of its proper divisors (2098620948677).

21115673765563 is a wasteful number, since it uses less digits than its factorization.

21115673765563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177079.

The product of its digits is 23814000, while the sum is 58.

The spelling of 21115673765563 in words is "twenty-one trillion, one hundred fifteen billion, six hundred seventy-three million, seven hundred sixty-five thousand, five hundred sixty-three".