21884893 has 4 divisors (see below), whose sum is σ = 22393888. Its totient is φ = 21375900.

The previous prime is 21884873. The next prime is 21884897. The reversal of 21884893 is 39848812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21884893 - 2⁵ = 21884861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 508951 = 21884893 / (2 + 1 + 8 + 8 + 4 + 8 + 9 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21884897) 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, 254433 + ... + 254518.

It is an arithmetic number, because the mean of its divisors is an integer number (5598472).

Almost surely, 2^21884893 is an apocalyptic number.

It is an amenable number.

21884893 is a deficient number, since it is larger than the sum of its proper divisors (508995).

21884893 is an equidigital number, since it uses as much as digits as its factorization.

21884893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 508994.

The product of its digits is 110592, while the sum is 43.

The square root of 21884893 is about 4678.1292201050. The cubic root of 21884893 is about 279.7143898889.

The spelling of 21884893 in words is "twenty-one million, eight hundred eighty-four thousand, eight hundred ninety-three".