23013821 has 2 divisors, whose sum is σ = 23013822. Its totient is φ = 23013820.

The previous prime is 23013799. The next prime is 23013827. The reversal of 23013821 is 12831032.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18369796 + 4644025 = 4286^2 + 2155^2 .

It is a cyclic number.

It is not a de Polignac number, because 23013821 - 2¹⁰ = 23012797 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 23013793 and 23013802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23013827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11506910 + 11506911.

It is an arithmetic number, because the mean of its divisors is an integer number (11506911).

Almost surely, 2^23013821 is an apocalyptic number.

It is an amenable number.

23013821 is a deficient number, since it is larger than the sum of its proper divisors (1).

23013821 is an equidigital number, since it uses as much as digits as its factorization.

23013821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 23013821 is about 4797.2722457663. The cubic root of 23013821 is about 284.4436504709.

Adding to 23013821 its reverse (12831032), we get a palindrome (35844853).

The spelling of 23013821 in words is "twenty-three million, thirteen thousand, eight hundred twenty-one".