21021221199 has 8 divisors (see below), whose sum is σ = 30576321792. Its totient is φ = 12740134040.

The previous prime is 21021221183. The next prime is 21021221209. The reversal of 21021221199 is 99112212012.

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

It is a cyclic number.

It is not a de Polignac number, because 21021221199 - 2⁴ = 21021221183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021221119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 318503319 + ... + 318503384.

It is an arithmetic number, because the mean of its divisors is an integer number (3822040224).

Almost surely, 2^21021221199 is an apocalyptic number.

21021221199 is a deficient number, since it is larger than the sum of its proper divisors (9555100593).

21021221199 is a wasteful number, since it uses less digits than its factorization.

21021221199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637006717.

The product of its (nonzero) digits is 1296, while the sum is 30.

It can be divided in two parts, 2 and 1021221199, that added together give a palindrome (1021221201).

The spelling of 21021221199 in words is "twenty-one billion, twenty-one million, two hundred twenty-one thousand, one hundred ninety-nine".