20958617 has 2 divisors, whose sum is σ = 20958618. Its totient is φ = 20958616.

The previous prime is 20958593. The next prime is 20958631. The reversal of 20958617 is 71685902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15217801 + 5740816 = 3901^2 + 2396^2 .

It is a cyclic number.

It is not a de Polignac number, because 20958617 - 2⁸ = 20958361 is a prime.

It is a super-3 number, since 3×20958617³ (a number of 23 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (20958517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10479308 + 10479309.

It is an arithmetic number, because the mean of its divisors is an integer number (10479309).

Almost surely, 2^20958617 is an apocalyptic number.

It is an amenable number.

20958617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20958617 is an equidigital number, since it uses as much as digits as its factorization.

20958617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 20958617 is about 4578.0582128234. The cubic root of 20958617 is about 275.7110721805.

The spelling of 20958617 in words is "twenty million, nine hundred fifty-eight thousand, six hundred seventeen".