21541626 has 40 divisors (see below), whose sum is σ = 48775584. Its totient is φ = 7105320.

The previous prime is 21541607. The next prime is 21541631. The reversal of 21541626 is 62614512.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 21541626.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 16041 + ... + 17331.

Almost surely, 2^21541626 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21541626, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24387792).

21541626 is an abundant number, since it is smaller than the sum of its proper divisors (27233958).

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

21541626 is a wasteful number, since it uses less digits than its factorization.

21541626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408 (or 1399 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 21541626 is about 4641.2957242563. The cubic root of 21541626 is about 278.2442258012.

The spelling of 21541626 in words is "twenty-one million, five hundred forty-one thousand, six hundred twenty-six".