21022093 has 2 divisors, whose sum is σ = 21022094. Its totient is φ = 21022092.

The previous prime is 21022091. The next prime is 21022097. The reversal of 21022093 is 39022012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20958084 + 64009 = 4578^2 + 253^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022093 - 2¹ = 21022091 is a prime.

Together with 21022091, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21022093.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21022091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511046 + 10511047.

It is an arithmetic number, because the mean of its divisors is an integer number (10511047).

Almost surely, 2^21022093 is an apocalyptic number.

It is an amenable number.

21022093 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022093 is an equidigital number, since it uses as much as digits as its factorization.

21022093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 21022093 is about 4584.9856052119. The cubic root of 21022093 is about 275.9891343829.

The spelling of 21022093 in words is "twenty-one million, twenty-two thousand, ninety-three".