21305514 has 16 divisors (see below), whose sum is σ = 42815520. Its totient is φ = 7067760.

The previous prime is 21305513. The next prime is 21305533. The reversal of 21305514 is 41550312.

It is not an unprimeable number, because it can be changed into a prime (21305513) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7149 + ... + 9680.

It is an arithmetic number, because the mean of its divisors is an integer number (2675970).

Almost surely, 2^21305514 is an apocalyptic number.

21305514 is an abundant number, since it is smaller than the sum of its proper divisors (21510006).

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

21305514 is a wasteful number, since it uses less digits than its factorization.

21305514 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17045.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21305514 is about 4615.7896399208. The cubic root of 21305514 is about 277.2239019971.

Adding to 21305514 its reverse (41550312), we get a palindrome (62855826).

The spelling of 21305514 in words is "twenty-one million, three hundred five thousand, five hundred fourteen".