21441918 has 32 divisors (see below), whose sum is σ = 45527040. Its totient is φ = 6713280.

The previous prime is 21441887. The next prime is 21441919. The reversal of 21441918 is 81914412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21441919) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13738 + ... + 15218.

It is an arithmetic number, because the mean of its divisors is an integer number (1422720).

Almost surely, 2^21441918 is an apocalyptic number.

21441918 is an abundant number, since it is smaller than the sum of its proper divisors (24085122).

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

21441918 is a wasteful number, since it uses less digits than its factorization.

21441918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1632.

The product of its digits is 2304, while the sum is 30.

The square root of 21441918 is about 4630.5418689393. The cubic root of 21441918 is about 277.8142661519.

The spelling of 21441918 in words is "twenty-one million, four hundred forty-one thousand, nine hundred eighteen".