21540332445 has 16 divisors (see below), whose sum is σ = 34466852160. Its totient is φ = 11487403904.

The previous prime is 21540332417. The next prime is 21540332453. The reversal of 21540332445 is 54423304512.

It is a cyclic number.

It is not a de Polignac number, because 21540332445 - 2⁶ = 21540332381 is a prime.

It is a super-2 number, since 2×21540332445² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235762 + ... + 314108.

It is an arithmetic number, because the mean of its divisors is an integer number (2154178260).

Almost surely, 2^21540332445 is an apocalyptic number.

It is an amenable number.

21540332445 is a deficient number, since it is larger than the sum of its proper divisors (12926519715).

21540332445 is a wasteful number, since it uses less digits than its factorization.

21540332445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96684.

The product of its (nonzero) digits is 57600, while the sum is 33.

Adding to 21540332445 its reverse (54423304512), we get a palindrome (75963636957).

The spelling of 21540332445 in words is "twenty-one billion, five hundred forty million, three hundred thirty-two thousand, four hundred forty-five".