20969513 has 2 divisors, whose sum is σ = 20969514. Its totient is φ = 20969512.

The previous prime is 20969497. The next prime is 20969527. The reversal of 20969513 is 31596902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17572864 + 3396649 = 4192^2 + 1843^2 .

It is a cyclic number.

It is not a de Polignac number, because 20969513 - 2⁴ = 20969497 is a prime.

It is not a weakly prime, because it can be changed into another prime (20969213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10484756 + 10484757.

It is an arithmetic number, because the mean of its divisors is an integer number (10484757).

Almost surely, 2^20969513 is an apocalyptic number.

It is an amenable number.

20969513 is a deficient number, since it is larger than the sum of its proper divisors (1).

20969513 is an equidigital number, since it uses as much as digits as its factorization.

20969513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 20969513 is about 4579.2480823821. The cubic root of 20969513 is about 275.7588429438.

The spelling of 20969513 in words is "twenty million, nine hundred sixty-nine thousand, five hundred thirteen".