21154535540564 has 12 divisors (see below), whose sum is σ = 37022752387488. Its totient is φ = 10576606287000.

The previous prime is 21154535540549. The next prime is 21154535540569. The reversal of 21154535540564 is 46504553545112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154535540569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165298862 + ... + 165426789.

It is an arithmetic number, because the mean of its divisors is an integer number (3085229365624).

Almost surely, 2^{21154535540564} is an apocalyptic number.

It is an amenable number.

21154535540564 is a deficient number, since it is larger than the sum of its proper divisors (15868216846924).

21154535540564 is a wasteful number, since it uses less digits than its factorization.

21154535540564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330741646 (or 330741644 counting only the distinct ones).

The product of its (nonzero) digits is 7200000, while the sum is 50.

The spelling of 21154535540564 in words is "twenty-one trillion, one hundred fifty-four billion, five hundred thirty-five million, five hundred forty thousand, five hundred sixty-four".