21873389 has 8 divisors (see below), whose sum is σ = 23250240. Its totient is φ = 20519136.

The previous prime is 21873361. The next prime is 21873409. The reversal of 21873389 is 98337812.

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 21873389 - 2¹⁶ = 21807853 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 (21873589) 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, 3632 + ... + 7545.

It is an arithmetic number, because the mean of its divisors is an integer number (2906280).

Almost surely, 2^21873389 is an apocalyptic number.

It is an amenable number.

21873389 is a deficient number, since it is larger than the sum of its proper divisors (1376851).

21873389 is a wasteful number, since it uses less digits than its factorization.

21873389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11299.

The product of its digits is 72576, while the sum is 41.

The square root of 21873389 is about 4676.8995071521. The cubic root of 21873389 is about 279.6653697980.

The spelling of 21873389 in words is "twenty-one million, eight hundred seventy-three thousand, three hundred eighty-nine".