1211011998198 has 16 divisors (see below), whose sum is σ = 2564495996400. Its totient is φ = 379925332736.

The previous prime is 1211011998193. The next prime is 1211011998211. The reversal of 1211011998198 is 8918991101121.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211011998198.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211011998193) 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 7 ways as a sum of consecutive naturals, for example, 5936333223 + ... + 5936333426.

It is an arithmetic number, because the mean of its divisors is an integer number (160280999775).

Almost surely, 2^{1211011998198} is an apocalyptic number.

1211011998198 is an abundant number, since it is smaller than the sum of its proper divisors (1353483998202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1211011998198 is a wasteful number, since it uses less digits than its factorization.

1211011998198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11872666671.

The product of its (nonzero) digits is 93312, while the sum is 51.

The spelling of 1211011998198 in words is "one trillion, two hundred eleven billion, eleven million, nine hundred ninety-eight thousand, one hundred ninety-eight".