1019111820091 has 16 divisors (see below), whose sum is σ = 1083919082400. Its totient is φ = 954852507648.

The previous prime is 1019111820079. The next prime is 1019111820113. The reversal of 1019111820091 is 1900281119101.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1019111820091 - 2¹⁹ = 1019111295803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1019111823091) 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, 3967320 + ... + 4216378.

It is an arithmetic number, because the mean of its divisors is an integer number (67744942650).

Almost surely, 2^{1019111820091} is an apocalyptic number.

1019111820091 is a deficient number, since it is larger than the sum of its proper divisors (64807262309).

1019111820091 is a wasteful number, since it uses less digits than its factorization.

1019111820091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250158.

The product of its (nonzero) digits is 1296, while the sum is 34.

Adding to 1019111820091 its reverse (1900281119101), we get a palindrome (2919392939192).

The spelling of 1019111820091 in words is "one trillion, nineteen billion, one hundred eleven million, eight hundred twenty thousand, ninety-one".