21112011999 has 24 divisors (see below), whose sum is σ = 33058424672. Its totient is φ = 12905956800.

The previous prime is 21112011917. The next prime is 21112012049. The reversal of 21112011999 is 99911021112.

It is not a de Polignac number, because 21112011999 - 2³¹ = 18964528351 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112051999) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 579832 + ... + 615165.

Almost surely, 2^21112011999 is an apocalyptic number.

21112011999 is a deficient number, since it is larger than the sum of its proper divisors (11946412673).

21112011999 is a wasteful number, since it uses less digits than its factorization.

21112011999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195167 (or 1195164 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 36.

The spelling of 21112011999 in words is "twenty-one billion, one hundred twelve million, eleven thousand, nine hundred ninety-nine".