21154836069 has 32 divisors (see below), whose sum is σ = 31778544000. Its totient is φ = 13906753920.

The previous prime is 21154836067. The next prime is 21154836089. The reversal of 21154836069 is 96063845112.

21154836069 is a `hidden beast` number, since 2 + 11 + 548 + 36 + 0 + 69 = 666.

It is not a de Polignac number, because 21154836069 - 2¹ = 21154836067 is a prime.

It is a super-2 number, since 2×21154836069² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154836067) 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, 1203657 + ... + 1221105.

It is an arithmetic number, because the mean of its divisors is an integer number (993079500).

Almost surely, 2^21154836069 is an apocalyptic number.

It is an amenable number.

21154836069 is a deficient number, since it is larger than the sum of its proper divisors (10623707931).

21154836069 is a wasteful number, since it uses less digits than its factorization.

21154836069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18082 (or 18076 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 21154836069 in words is "twenty-one billion, one hundred fifty-four million, eight hundred thirty-six thousand, sixty-nine".