21514307 has 4 divisors (see below), whose sum is σ = 21786720. Its totient is φ = 21241896.

The previous prime is 21514301. The next prime is 21514369. The reversal of 21514307 is 70341512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21514307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21514301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136088 + ... + 136245.

It is an arithmetic number, because the mean of its divisors is an integer number (5446680).

Almost surely, 2^21514307 is an apocalyptic number.

21514307 is a deficient number, since it is larger than the sum of its proper divisors (272413).

21514307 is an equidigital number, since it uses as much as digits as its factorization.

21514307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272412.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 21514307 is about 4638.3517546646. The cubic root of 21514307 is about 278.1265533221.

Adding to 21514307 its reverse (70341512), we get a palindrome (91855819).

The spelling of 21514307 in words is "twenty-one million, five hundred fourteen thousand, three hundred seven".