21342199999 has 4 divisors (see below), whose sum is σ = 22078137960. Its totient is φ = 20606262040.

The previous prime is 21342199987. The next prime is 21342200039. The reversal of 21342199999 is 99999124312.

It is a happy number.

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

It is not a de Polignac number, because 21342199999 - 2¹⁷ = 21342068927 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21342199979) 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, 367968937 + ... + 367968994.

It is an arithmetic number, because the mean of its divisors is an integer number (5519534490).

Almost surely, 2^21342199999 is an apocalyptic number.

21342199999 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21342199999 is a deficient number, since it is larger than the sum of its proper divisors (735937961).

21342199999 is an equidigital number, since it uses as much as digits as its factorization.

21342199999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735937960.

The product of its digits is 2834352, while the sum is 58.

The spelling of 21342199999 in words is "twenty-one billion, three hundred forty-two million, one hundred ninety-nine thousand, nine hundred ninety-nine".