21241704 has 64 divisors (see below), whose sum is σ = 61352640. Its totient is φ = 6056960.

The previous prime is 21241667. The next prime is 21241723. The reversal of 21241704 is 40714212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2122 + ... + 6854.

It is an arithmetic number, because the mean of its divisors is an integer number (958635).

Almost surely, 2^21241704 is an apocalyptic number.

21241704 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21241704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30676320).

21241704 is an abundant number, since it is smaller than the sum of its proper divisors (40110936).

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

21241704 is a wasteful number, since it uses less digits than its factorization.

21241704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4770 (or 4766 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 21241704 is about 4608.8723132671. The cubic root of 21241704 is about 276.9468634364.

Adding to 21241704 its reverse (40714212), we get a palindrome (61955916).

It can be divided in two parts, 21241 and 704, that added together give a triangular number (21945 = T₂₀₉).

The spelling of 21241704 in words is "twenty-one million, two hundred forty-one thousand, seven hundred four".