21871130 has 8 divisors (see below), whose sum is σ = 39368052. Its totient is φ = 8748448.

The previous prime is 21871117. The next prime is 21871141. The reversal of 21871130 is 3117812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21279769 + 591361 = 4613^2 + 769^2 .

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21871096 and 21871105.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1093547 + ... + 1093566.

Almost surely, 2^21871130 is an apocalyptic number.

21871130 is a deficient number, since it is larger than the sum of its proper divisors (17496922).

21871130 is a wasteful number, since it uses less digits than its factorization.

21871130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2187120.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 21871130 is about 4676.6579947651. The cubic root of 21871130 is about 279.6557418764.

Adding to 21871130 its reverse (3117812), we get a palindrome (24988942).

The spelling of 21871130 in words is "twenty-one million, eight hundred seventy-one thousand, one hundred thirty".