21876871 has 2 divisors, whose sum is σ = 21876872. Its totient is φ = 21876870.

The previous prime is 21876839. The next prime is 21876901. The reversal of 21876871 is 17867812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21876871 - 2⁵ = 21876839 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21846871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10938435 + 10938436.

It is an arithmetic number, because the mean of its divisors is an integer number (10938436).

Almost surely, 2^21876871 is an apocalyptic number.

21876871 is a deficient number, since it is larger than the sum of its proper divisors (1).

21876871 is an equidigital number, since it uses as much as digits as its factorization.

21876871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37632, while the sum is 40.

The square root of 21876871 is about 4677.2717475041. The cubic root of 21876871 is about 279.6802088816.

The spelling of 21876871 in words is "twenty-one million, eight hundred seventy-six thousand, eight hundred seventy-one".