21412823 has 2 divisors, whose sum is σ = 21412824. Its totient is φ = 21412822.

The previous prime is 21412801. The next prime is 21412837. The reversal of 21412823 is 32821412.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21412823 - 2¹² = 21408727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21412883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10706411 + 10706412.

It is an arithmetic number, because the mean of its divisors is an integer number (10706412).

Almost surely, 2^21412823 is an apocalyptic number.

21412823 is a deficient number, since it is larger than the sum of its proper divisors (1).

21412823 is an equidigital number, since it uses as much as digits as its factorization.

21412823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 768, while the sum is 23.

The square root of 21412823 is about 4627.3991615161. The cubic root of 21412823 is about 277.6885518877.

The spelling of 21412823 in words is "twenty-one million, four hundred twelve thousand, eight hundred twenty-three".