21748087 has 8 divisors (see below), whose sum is σ = 23006304. Its totient is φ = 20515968.

The previous prime is 21748063. The next prime is 21748091. The reversal of 21748087 is 78084712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21748087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21748687) 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, 4798 + ... + 8155.

It is an arithmetic number, because the mean of its divisors is an integer number (2875788).

Almost surely, 2^21748087 is an apocalyptic number.

21748087 is a deficient number, since it is larger than the sum of its proper divisors (1258217).

21748087 is a wasteful number, since it uses less digits than its factorization.

21748087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13049.

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 21748087 is about 4663.4844269066. The cubic root of 21748087 is about 279.1303245580.

The spelling of 21748087 in words is "twenty-one million, seven hundred forty-eight thousand, eighty-seven".