19956288265991 has 16 divisors (see below), whose sum is σ = 25962330981888. Its totient is φ = 14874252122400.

The previous prime is 19956288265891. The next prime is 19956288266023.

19956288265991 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 19956288265991 - 2²² = 19956284071687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19956288265891) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5634184640 + ... + 5634188181.

It is an arithmetic number, because the mean of its divisors is an integer number (1622645686368).

Almost surely, 2^{19956288265991} is an apocalyptic number.

19956288265991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

19956288265991 is a deficient number, since it is larger than the sum of its proper divisors (6006042715897).

19956288265991 is a wasteful number, since it uses less digits than its factorization.

19956288265991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11268372862.

The product of its digits is 1511654400, while the sum is 80.

The spelling of 19956288265991 in words is "nineteen trillion, nine hundred fifty-six billion, two hundred eighty-eight million, two hundred sixty-five thousand, nine hundred ninety-one".