10981999191 has 4 divisors (see below), whose sum is σ = 14642665592. Its totient is φ = 7321332792.

The previous prime is 10981999187. The next prime is 10981999211. The reversal of 10981999191 is 19199918901.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 10981999191 - 2² = 10981999187 is a prime.

It is a super-2 number, since 2×10981999191² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10981999111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1830333196 + ... + 1830333201.

It is an arithmetic number, because the mean of its divisors is an integer number (3660666398).

Almost surely, 2^10981999191 is an apocalyptic number.

10981999191 is a deficient number, since it is larger than the sum of its proper divisors (3660666401).

10981999191 is an equidigital number, since it uses as much as digits as its factorization.

10981999191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3660666400.

The product of its (nonzero) digits is 472392, while the sum is 57.

The spelling of 10981999191 in words is "ten billion, nine hundred eighty-one million, nine hundred ninety-nine thousand, one hundred ninety-one".