21458899 has 8 divisors (see below), whose sum is σ = 26754048. Its totient is φ = 16721160.

The previous prime is 21458893. The next prime is 21458909. The reversal of 21458899 is 99885412.

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 21458899 - 2⁹ = 21458387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21458893) 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, 139267 + ... + 139420.

It is an arithmetic number, because the mean of its divisors is an integer number (3344256).

Almost surely, 2^21458899 is an apocalyptic number.

21458899 is a deficient number, since it is larger than the sum of its proper divisors (5295149).

21458899 is a wasteful number, since it uses less digits than its factorization.

21458899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278705.

The product of its digits is 207360, while the sum is 46.

The square root of 21458899 is about 4632.3750927575. The cubic root of 21458899 is about 277.8875854517.

It can be divided in two parts, 214588 and 99, that multiplied together give a palindrome (21244212).

The spelling of 21458899 in words is "twenty-one million, four hundred fifty-eight thousand, eight hundred ninety-nine".