21885436 has 6 divisors (see below), whose sum is σ = 38299520. Its totient is φ = 10942716.

The previous prime is 21885427. The next prime is 21885439. The reversal of 21885436 is 63458812.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21885395 and 21885404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21885439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2735676 + ... + 2735683.

Almost surely, 2^21885436 is an apocalyptic number.

It is an amenable number.

21885436 is a deficient number, since it is larger than the sum of its proper divisors (16414084).

21885436 is a wasteful number, since it uses less digits than its factorization.

21885436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5471363 (or 5471361 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 21885436 is about 4678.1872557648. The cubic root of 21885436 is about 279.7167032603.

The spelling of 21885436 in words is "twenty-one million, eight hundred eighty-five thousand, four hundred thirty-six".