1819091820091 has 12 divisors (see below), whose sum is σ = 2278862280912. Its totient is φ = 1439281439568.

The previous prime is 1819091820067. The next prime is 1819091820103. The reversal of 1819091820091 is 1900281909181.

It is a happy number.

It is not a de Polignac number, because 1819091820091 - 2⁵ = 1819091820059 is a prime.

It is a super-2 number, since 2×1819091820091² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (1819091820391) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1427857935 + ... + 1427859208.

It is an arithmetic number, because the mean of its divisors is an integer number (189905190076).

Almost surely, 2^{1819091820091} is an apocalyptic number.

1819091820091 is a deficient number, since it is larger than the sum of its proper divisors (459770460821).

1819091820091 is a wasteful number, since it uses less digits than its factorization.

1819091820091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2855717170 (or 2855717163 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 49.

The spelling of 1819091820091 in words is "one trillion, eight hundred nineteen billion, ninety-one million, eight hundred twenty thousand, ninety-one".