21553072449 has 8 divisors (see below), whose sum is σ = 29405742432. Its totient is φ = 14034558720.

The previous prime is 21553072433. The next prime is 21553072451. The reversal of 21553072449 is 94427035512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21553072449 - 2⁴ = 21553072433 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21553072449.

It is not an unprimeable number, because it can be changed into a prime (21553072469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83538912 + ... + 83539169.

It is an arithmetic number, because the mean of its divisors is an integer number (3675717804).

Almost surely, 2^21553072449 is an apocalyptic number.

It is an amenable number.

21553072449 is a deficient number, since it is larger than the sum of its proper divisors (7852669983).

21553072449 is a wasteful number, since it uses less digits than its factorization.

21553072449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167078127.

The product of its (nonzero) digits is 302400, while the sum is 42.

The spelling of 21553072449 in words is "twenty-one billion, five hundred fifty-three million, seventy-two thousand, four hundred forty-nine".