20959513 has 2 divisors, whose sum is σ = 20959514. Its totient is φ = 20959512.

The previous prime is 20959511. The next prime is 20959517. The reversal of 20959513 is 31595902.

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., 13046544 + 7912969 = 3612^2 + 2813^2 .

It is a cyclic number.

It is not a de Polignac number, because 20959513 - 2¹ = 20959511 is a prime.

Together with 20959511, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20959511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10479756 + 10479757.

It is an arithmetic number, because the mean of its divisors is an integer number (10479757).

Almost surely, 2^20959513 is an apocalyptic number.

It is an amenable number.

20959513 is a deficient number, since it is larger than the sum of its proper divisors (1).

20959513 is an equidigital number, since it uses as much as digits as its factorization.

20959513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12150, while the sum is 34.

The square root of 20959513 is about 4578.1560698604. The cubic root of 20959513 is about 275.7150010912.

The spelling of 20959513 in words is "twenty million, nine hundred fifty-nine thousand, five hundred thirteen".