20858618813 has 2 divisors, whose sum is σ = 20858618814. Its totient is φ = 20858618812.

The previous prime is 20858618747. The next prime is 20858618839. The reversal of 20858618813 is 31881685802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17736379684 + 3122239129 = 133178^2 + 55877^2 .

It is a cyclic number.

It is not a de Polignac number, because 20858618813 - 2¹² = 20858614717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20858618113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10429309406 + 10429309407.

It is an arithmetic number, because the mean of its divisors is an integer number (10429309407).

Almost surely, 2^20858618813 is an apocalyptic number.

It is an amenable number.

20858618813 is a deficient number, since it is larger than the sum of its proper divisors (1).

20858618813 is an equidigital number, since it uses as much as digits as its factorization.

20858618813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 737280, while the sum is 50.

The spelling of 20858618813 in words is "twenty billion, eight hundred fifty-eight million, six hundred eighteen thousand, eight hundred thirteen".