19869696891 has 36 divisors (see below), whose sum is σ = 31564181376. Its totient is φ = 12035691360.

The previous prime is 19869696881. The next prime is 19869696901.

19869696891 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (19869696881) and next prime (19869696901).

It is not a de Polignac number, because 19869696891 - 2⁵ = 19869696859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19869696851) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2650150 + ... + 2657636.

It is an arithmetic number, because the mean of its divisors is an integer number (876782816).

Almost surely, 2^19869696891 is an apocalyptic number.

19869696891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

19869696891 is a deficient number, since it is larger than the sum of its proper divisors (11694484485).

19869696891 is a wasteful number, since it uses less digits than its factorization.

19869696891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9952 (or 9938 counting only the distinct ones).

The product of its digits is 90699264, while the sum is 72.

It can be divided in two parts, 19869696 and 891, that multiplied together give a square (17703899136 = 133056²).

The spelling of 19869696891 in words is "nineteen billion, eight hundred sixty-nine million, six hundred ninety-six thousand, eight hundred ninety-one".