20863613 has 2 divisors, whose sum is σ = 20863614. Its totient is φ = 20863612.

The previous prime is 20863603. The next prime is 20863621. The reversal of 20863613 is 31636802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20313049 + 550564 = 4507^2 + 742^2 .

It is a cyclic number.

It is not a de Polignac number, because 20863613 - 2¹⁶ = 20798077 is a prime.

It is equal to p_1321877 and since 20863613 and 1321877 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20863603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10431806 + 10431807.

It is an arithmetic number, because the mean of its divisors is an integer number (10431807).

Almost surely, 2^20863613 is an apocalyptic number.

It is an amenable number.

20863613 is a deficient number, since it is larger than the sum of its proper divisors (1).

20863613 is an equidigital number, since it uses as much as digits as its factorization.

20863613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 20863613 is about 4567.6704128034. The cubic root of 20863613 is about 275.2938478841.

The spelling of 20863613 in words is "twenty million, eight hundred sixty-three thousand, six hundred thirteen".