21398199 has 8 divisors (see below), whose sum is σ = 30032640. Its totient is φ = 13514616.

The previous prime is 21398191. The next prime is 21398227. The reversal of 21398199 is 99189312.

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

It is not a de Polignac number, because 21398199 - 2³ = 21398191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21398199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21398191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187647 + ... + 187760.

It is an arithmetic number, because the mean of its divisors is an integer number (3754080).

Almost surely, 2^21398199 is an apocalyptic number.

21398199 is a deficient number, since it is larger than the sum of its proper divisors (8634441).

21398199 is a wasteful number, since it uses less digits than its factorization.

21398199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375429.

The product of its digits is 34992, while the sum is 42.

The square root of 21398199 is about 4625.8187383424. The cubic root of 21398199 is about 277.6253212057.

The spelling of 21398199 in words is "twenty-one million, three hundred ninety-eight thousand, one hundred ninety-nine".