21214704 has 80 divisors (see below), whose sum is σ = 63345152. Its totient is φ = 5992704.

The previous prime is 21214703. The next prime is 21214741. The reversal of 21214704 is 40741212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21214703) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 34302 + ... + 34914.

Almost surely, 2^21214704 is an apocalyptic number.

21214704 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 21214704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31672576).

21214704 is an abundant number, since it is smaller than the sum of its proper divisors (42130448).

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

21214704 is a wasteful number, since it uses less digits than its factorization.

21214704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734 (or 728 counting only the distinct ones).

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

The square root of 21214704 is about 4605.9422488781. The cubic root of 21214704 is about 276.8294727324.

Adding to 21214704 its reverse (40741212), we get a palindrome (61955916).

The spelling of 21214704 in words is "twenty-one million, two hundred fourteen thousand, seven hundred four".