21331486 has 16 divisors (see below), whose sum is σ = 35054208. Its totient is φ = 9655000.

The previous prime is 21331477. The next prime is 21331487. The reversal of 21331486 is 68413312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331487) 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, 3591 + ... + 7453.

It is an arithmetic number, because the mean of its divisors is an integer number (2190888).

Almost surely, 2^21331486 is an apocalyptic number.

21331486 is a deficient number, since it is larger than the sum of its proper divisors (13722722).

21331486 is a wasteful number, since it uses less digits than its factorization.

21331486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4127.

The product of its digits is 3456, while the sum is 28.

The square root of 21331486 is about 4618.6021694881. The cubic root of 21331486 is about 277.3365040755.

Adding to 21331486 its reverse (68413312), we get a palindrome (89744798).

The spelling of 21331486 in words is "twenty-one million, three hundred thirty-one thousand, four hundred eighty-six".