21014784 has 108 divisors (see below), whose sum is σ = 69299776. Its totient is φ = 5999616.

The previous prime is 21014761. The next prime is 21014803. The reversal of 21014784 is 48741012.

It is a super-2 number, since 2×21014784² = 883242293133312, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15477 + ... + 16779.

Almost surely, 2^21014784 is an apocalyptic number.

21014784 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 21014784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34649888).

21014784 is an abundant number, since it is smaller than the sum of its proper divisors (48284992).

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

21014784 is a wasteful number, since it uses less digits than its factorization.

21014784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1332 (or 1315 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 21014784 is about 4584.1884778006. The cubic root of 21014784 is about 275.9571452051.

Adding to 21014784 its reverse (48741012), we get a palindrome (69755796).

The spelling of 21014784 in words is "twenty-one million, fourteen thousand, seven hundred eighty-four".