21012413 has 2 divisors, whose sum is σ = 21012414. Its totient is φ = 21012412.

The previous prime is 21012401. The next prime is 21012419. The reversal of 21012413 is 31421012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20994724 + 17689 = 4582^2 + 133^2 .

It is a cyclic number.

It is not a de Polignac number, because 21012413 - 2⁶ = 21012349 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 (21012419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506206 + 10506207.

It is an arithmetic number, because the mean of its divisors is an integer number (10506207).

Almost surely, 2^21012413 is an apocalyptic number.

It is an amenable number.

21012413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012413 is an equidigital number, since it uses as much as digits as its factorization.

21012413 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21012413 is about 4583.9298642104. The cubic root of 21012413 is about 275.9467664958.

Adding to 21012413 its reverse (31421012), we get a palindrome (52433425).

The spelling of 21012413 in words is "twenty-one million, twelve thousand, four hundred thirteen".