21325013 has 2 divisors, whose sum is σ = 21325014. Its totient is φ = 21325012.

The previous prime is 21324983. The next prime is 21325037. The reversal of 21325013 is 31052312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17783089 + 3541924 = 4217^2 + 1882^2 .

It is a cyclic number.

It is not a de Polignac number, because 21325013 - 2⁶ = 21324949 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21324982 and 21325000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21325093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10662506 + 10662507.

It is an arithmetic number, because the mean of its divisors is an integer number (10662507).

Almost surely, 2^21325013 is an apocalyptic number.

It is an amenable number.

21325013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21325013 is an equidigital number, since it uses as much as digits as its factorization.

21325013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 21325013 is about 4617.9013631735. The cubic root of 21325013 is about 277.3084488210.

Adding to 21325013 its reverse (31052312), we get a palindrome (52377325).

The spelling of 21325013 in words is "twenty-one million, three hundred twenty-five thousand, thirteen".