21486426 has 32 divisors (see below), whose sum is σ = 47271168. Its totient is φ = 6469440.

The previous prime is 21486403. The next prime is 21486433. The reversal of 21486426 is 62468412.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 736 + ... + 6596.

It is an arithmetic number, because the mean of its divisors is an integer number (1477224).

Almost surely, 2^21486426 is an apocalyptic number.

21486426 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21486426, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23635584).

21486426 is an abundant number, since it is smaller than the sum of its proper divisors (25784742).

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

21486426 is a wasteful number, since it uses less digits than its factorization.

21486426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5926.

The product of its digits is 18432, while the sum is 33.

The square root of 21486426 is about 4635.3452945816. The cubic root of 21486426 is about 278.0063573585.

It can be divided in two parts, 21486 and 426, that added together give a palindrome (21912).

The spelling of 21486426 in words is "twenty-one million, four hundred eighty-six thousand, four hundred twenty-six".