21489975045 has 48 divisors (see below), whose sum is σ = 46440680832. Its totient is φ = 8930897280.

The previous prime is 21489974983. The next prime is 21489975047. The reversal of 21489975045 is 54057998412.

It is a happy number.

21489975045 is a `hidden beast` number, since 2 + 1 + 48 + 9 + 97 + 504 + 5 = 666.

It is not a de Polignac number, because 21489975045 - 2¹⁰ = 21489974021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21489974982 and 21489975000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21489975047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3097542 + ... + 3104471.

It is an arithmetic number, because the mean of its divisors is an integer number (967514184).

Almost surely, 2^21489975045 is an apocalyptic number.

It is an amenable number.

21489975045 is an abundant number, since it is smaller than the sum of its proper divisors (24950705787).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21489975045 is a wasteful number, since it uses less digits than its factorization.

21489975045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6202042 (or 6202039 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 54.

The spelling of 21489975045 in words is "twenty-one billion, four hundred eighty-nine million, nine hundred seventy-five thousand, forty-five".