21310193 has 2 divisors, whose sum is σ = 21310194. Its totient is φ = 21310192.

The previous prime is 21310189. The next prime is 21310199. The reversal of 21310193 is 39101312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21086464 + 223729 = 4592^2 + 473^2 .

It is a cyclic number.

It is not a de Polignac number, because 21310193 - 2² = 21310189 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21310199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655096 + 10655097.

It is an arithmetic number, because the mean of its divisors is an integer number (10655097).

Almost surely, 2^21310193 is an apocalyptic number.

It is an amenable number.

21310193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21310193 is an equidigital number, since it uses as much as digits as its factorization.

21310193 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 21310193 is about 4616.2964592842. The cubic root of 21310193 is about 277.2441946420.

The spelling of 21310193 in words is "twenty-one million, three hundred ten thousand, one hundred ninety-three".