21898343 has 4 divisors (see below), whose sum is σ = 21909888. Its totient is φ = 21886800.

The previous prime is 21898337. The next prime is 21898351. The reversal of 21898343 is 34389812.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21898343 - 2⁸ = 21898087 is a prime.

It is a super-2 number, since 2×21898343² = 959074852291298, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21898297 and 21898306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21898313) 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, 2183 + ... + 6968.

It is an arithmetic number, because the mean of its divisors is an integer number (5477472).

Almost surely, 2^21898343 is an apocalyptic number.

21898343 is a deficient number, since it is larger than the sum of its proper divisors (11545).

21898343 is an equidigital number, since it uses as much as digits as its factorization.

21898343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11544.

The product of its digits is 41472, while the sum is 38.

The square root of 21898343 is about 4679.5665397556. The cubic root of 21898343 is about 279.7716803692.

The spelling of 21898343 in words is "twenty-one million, eight hundred ninety-eight thousand, three hundred forty-three".