21489019199 has 4 divisors (see below), whose sum is σ = 21527188536. Its totient is φ = 21450849864.

The previous prime is 21489019157. The next prime is 21489019213. The reversal of 21489019199 is 99191098412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21489019199 - 2¹² = 21489015103 is a prime.

It is a super-2 number, since 2×21489019199² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21489019199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21489019109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19083824 + ... + 19084949.

It is an arithmetic number, because the mean of its divisors is an integer number (5381797134).

Almost surely, 2^21489019199 is an apocalyptic number.

21489019199 is a deficient number, since it is larger than the sum of its proper divisors (38169337).

21489019199 is an equidigital number, since it uses as much as digits as its factorization.

21489019199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38169336.

The product of its (nonzero) digits is 419904, while the sum is 53.

The spelling of 21489019199 in words is "twenty-one billion, four hundred eighty-nine million, nineteen thousand, one hundred ninety-nine".