21888143 has 4 divisors (see below), whose sum is σ = 21927048. Its totient is φ = 21849240.

The previous prime is 21888131. The next prime is 21888151. The reversal of 21888143 is 34188812.

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

It is a cyclic number.

It is not a de Polignac number, because 21888143 - 2¹⁰ = 21887119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21888103) 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, 18596 + ... + 19737.

It is an arithmetic number, because the mean of its divisors is an integer number (5481762).

Almost surely, 2^21888143 is an apocalyptic number.

21888143 is a deficient number, since it is larger than the sum of its proper divisors (38905).

21888143 is an equidigital number, since it uses as much as digits as its factorization.

21888143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38904.

The product of its digits is 12288, while the sum is 35.

The square root of 21888143 is about 4678.4765682859. The cubic root of 21888143 is about 279.7282354637.

The spelling of 21888143 in words is "twenty-one million, eight hundred eighty-eight thousand, one hundred forty-three".