21361884 has 24 divisors (see below), whose sum is σ = 51004800. Its totient is φ = 6954864.

The previous prime is 21361853. The next prime is 21361889. The reversal of 21361884 is 48816312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21361889) 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, 20184 + ... + 21215.

It is an arithmetic number, because the mean of its divisors is an integer number (2125200).

Almost surely, 2^21361884 is an apocalyptic number.

It is an amenable number.

21361884 is an abundant number, since it is smaller than the sum of its proper divisors (29642916).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21361884 is a wasteful number, since it uses less digits than its factorization.

21361884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41449 (or 41447 counting only the distinct ones).

The product of its digits is 9216, while the sum is 33.

The square root of 21361884 is about 4621.8918204562. The cubic root of 21361884 is about 277.4681791286.

The spelling of 21361884 in words is "twenty-one million, three hundred sixty-one thousand, eight hundred eighty-four".