21318627 has 32 divisors (see below), whose sum is σ = 33027840. Its totient is φ = 12196800.

The previous prime is 21318599. The next prime is 21318643. The reversal of 21318627 is 72681312.

It is not a de Polignac number, because 21318627 - 2¹¹ = 21316579 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

Its product of digits (4032) is a multiple of the sum of its prime factors (336).

It is a junction number, because it is equal to n+sod(n) for n = 21318594 and 21318603.

It is not an unprimeable number, because it can be changed into a prime (21318727) 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 31 ways as a sum of consecutive naturals, for example, 75727 + ... + 76007.

It is an arithmetic number, because the mean of its divisors is an integer number (1032120).

Almost surely, 2^21318627 is an apocalyptic number.

21318627 is a deficient number, since it is larger than the sum of its proper divisors (11709213).

21318627 is a wasteful number, since it uses less digits than its factorization.

21318627 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 314 counting only the distinct ones).

The product of its digits is 4032, while the sum is 30.

The square root of 21318627 is about 4617.2098717732. The cubic root of 21318627 is about 277.2807650777.

Adding to 21318627 its reverse (72681312), we get a palindrome (93999939).

It can be divided in two parts, 21318 and 627, that added together give a triangular number (21945 = T₂₀₉).

The spelling of 21318627 in words is "twenty-one million, three hundred eighteen thousand, six hundred twenty-seven".