21888789 has 8 divisors (see below), whose sum is σ = 31430112. Its totient is φ = 13470000.

The previous prime is 21888787. The next prime is 21888827. The reversal of 21888789 is 98788812.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21888789 - 2¹ = 21888787 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21888787) 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, 280587 + ... + 280664.

It is an arithmetic number, because the mean of its divisors is an integer number (3928764).

Almost surely, 2^21888789 is an apocalyptic number.

It is an amenable number.

21888789 is a deficient number, since it is larger than the sum of its proper divisors (9541323).

21888789 is a wasteful number, since it uses less digits than its factorization.

21888789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561267.

The product of its digits is 516096, while the sum is 51.

The square root of 21888789 is about 4678.5456073442. The cubic root of 21888789 is about 279.7309873747.

The spelling of 21888789 in words is "twenty-one million, eight hundred eighty-eight thousand, seven hundred eighty-nine".