19999902851 has 2 divisors, whose sum is σ = 19999902852. Its totient is φ = 19999902850.

The previous prime is 19999902847. The next prime is 19999902877. The reversal of 19999902851 is 15820999991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19999902851 - 2² = 19999902847 is a prime.

It is a super-2 number, since 2×19999902851² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19999901851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9999951425 + 9999951426.

It is an arithmetic number, because the mean of its divisors is an integer number (9999951426).

Almost surely, 2^19999902851 is an apocalyptic number.

19999902851 is a deficient number, since it is larger than the sum of its proper divisors (1).

19999902851 is an equidigital number, since it uses as much as digits as its factorization.

19999902851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4723920, while the sum is 62.

The spelling of 19999902851 in words is "nineteen billion, nine hundred ninety-nine million, nine hundred two thousand, eight hundred fifty-one".