91781443419 has 16 divisors (see below), whose sum is σ = 124590919200. Its totient is φ = 60089734656.

The previous prime is 91781443399. The next prime is 91781443421. The reversal of 91781443419 is 91434418719.

It is a de Polignac number, because none of the positive numbers 2^k-91781443419 is a prime.

It is a super-2 number, since 2×91781443419² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91781443319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1204984 + ... + 1278885.

It is an arithmetic number, because the mean of its divisors is an integer number (7786932450).

Almost surely, 2^91781443419 is an apocalyptic number.

91781443419 is a deficient number, since it is larger than the sum of its proper divisors (32809475781).

91781443419 is a wasteful number, since it uses less digits than its factorization.

91781443419 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2484094.

The product of its digits is 870912, while the sum is 51.

The spelling of 91781443419 in words is "ninety-one billion, seven hundred eighty-one million, four hundred forty-three thousand, four hundred nineteen".