19918692851 has 2 divisors, whose sum is σ = 19918692852. Its totient is φ = 19918692850.

The previous prime is 19918692847. The next prime is 19918692877. The reversal of 19918692851 is 15829681991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19918692851 - 2² = 19918692847 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (19918692151) 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, 9959346425 + 9959346426.

It is an arithmetic number, because the mean of its divisors is an integer number (9959346426).

Almost surely, 2^19918692851 is an apocalyptic number.

19918692851 is a deficient number, since it is larger than the sum of its proper divisors (1).

19918692851 is an equidigital number, since it uses as much as digits as its factorization.

19918692851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2799360, while the sum is 59.

The spelling of 19918692851 in words is "nineteen billion, nine hundred eighteen million, six hundred ninety-two thousand, eight hundred fifty-one".