21360087 has 12 divisors (see below), whose sum is σ = 35261200. Its totient is φ = 12205728.

The previous prime is 21360083. The next prime is 21360107. The reversal of 21360087 is 78006312.

It is not a de Polignac number, because 21360087 - 2² = 21360083 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21360087.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21360083) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 169462 + ... + 169587.

Almost surely, 2^21360087 is an apocalyptic number.

21360087 is a deficient number, since it is larger than the sum of its proper divisors (13901113).

21360087 is a wasteful number, since it uses less digits than its factorization.

21360087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339062 (or 339059 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21360087 is about 4621.6974154525. The cubic root of 21360087 is about 277.4603985368.

Adding to 21360087 its reverse (78006312), we get a palindrome (99366399).

The spelling of 21360087 in words is "twenty-one million, three hundred sixty thousand, eighty-seven".