21369544 has 32 divisors (see below), whose sum is σ = 48487680. Its totient is φ = 8619264.

The previous prime is 21369533. The next prime is 21369577. The reversal of 21369544 is 44596312.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10272 + ... + 12175.

It is an arithmetic number, because the mean of its divisors is an integer number (1515240).

Almost surely, 2^21369544 is an apocalyptic number.

It is an amenable number.

21369544 is an abundant number, since it is smaller than the sum of its proper divisors (27118136).

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

21369544 is a wasteful number, since it uses less digits than its factorization.

21369544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22477 (or 22473 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 21369544 is about 4622.7204111865. The cubic root of 21369544 is about 277.5013402527.

The spelling of 21369544 in words is "twenty-one million, three hundred sixty-nine thousand, five hundred forty-four".