21219748899 has 64 divisors (see below), whose sum is σ = 30780948480. Its totient is φ = 12975500160.

The previous prime is 21219748897. The next prime is 21219748903. The reversal of 21219748899 is 99884791212.

It is a happy number.

It is a Cunningham number, because it is equal to 145670²-1.

It is not a de Polignac number, because 21219748899 - 2¹ = 21219748897 is a prime.

It is a super-2 number, since 2×21219748899² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21219748897) 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 63 ways as a sum of consecutive naturals, for example, 25783002 + ... + 25783824.

It is an arithmetic number, because the mean of its divisors is an integer number (480952320).

Almost surely, 2^21219748899 is an apocalyptic number.

21219748899 is a deficient number, since it is larger than the sum of its proper divisors (9561199581).

21219748899 is a wasteful number, since it uses less digits than its factorization.

21219748899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080.

The product of its digits is 5225472, while the sum is 60.

The spelling of 21219748899 in words is "twenty-one billion, two hundred nineteen million, seven hundred forty-eight thousand, eight hundred ninety-nine".