20858544851 has 2 divisors, whose sum is σ = 20858544852. Its totient is φ = 20858544850.

The previous prime is 20858544739. The next prime is 20858544887. The reversal of 20858544851 is 15844585802.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20858544851 is a prime.

It is a super-2 number, since 2×20858544851² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20858544851.

It is not a weakly prime, because it can be changed into another prime (20858504851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10429272425 + 10429272426.

It is an arithmetic number, because the mean of its divisors is an integer number (10429272426).

Almost surely, 2^20858544851 is an apocalyptic number.

20858544851 is a deficient number, since it is larger than the sum of its proper divisors (1).

20858544851 is an equidigital number, since it uses as much as digits as its factorization.

20858544851 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2048000, while the sum is 50.

The spelling of 20858544851 in words is "twenty billion, eight hundred fifty-eight million, five hundred forty-four thousand, eight hundred fifty-one".