20818969578099 has 120 divisors (see below), whose sum is σ = 39075328328960. Its totient is φ = 10812936356640.

The previous prime is 20818969578091. The next prime is 20818969578133. The reversal of 20818969578099 is 99087596981802.

20818969578099 is a `hidden beast` number, since 20 + 8 + 18 + 9 + 6 + 9 + 578 + 0 + 9 + 9 = 666.

It is not a de Polignac number, because 20818969578099 - 2³ = 20818969578091 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (20818969578091) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 388220202 + ... + 388273824.

Almost surely, 2^{20818969578099} is an apocalyptic number.

20818969578099 is a deficient number, since it is larger than the sum of its proper divisors (18256358750861).

20818969578099 is a wasteful number, since it uses less digits than its factorization.

20818969578099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59323 (or 59303 counting only the distinct ones).

The product of its (nonzero) digits is 1410877440, while the sum is 81.

The spelling of 20818969578099 in words is "twenty trillion, eight hundred eighteen billion, nine hundred sixty-nine million, five hundred seventy-eight thousand, ninety-nine".