1661199119 has 2 divisors, whose sum is σ = 1661199120. Its totient is φ = 1661199118.

The previous prime is 1661199109. The next prime is 1661199121. The reversal of 1661199119 is 9119911661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1661199119 - 2²⁸ = 1392763663 is a prime.

It is a super-2 number, since 2×1661199119² = 5519165025932752322, which contains 22 as substring.

Together with 1661199121, it forms a pair of twin primes.

It is a Chen prime.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 1661199119.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661199109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830599559 + 830599560.

It is an arithmetic number, because the mean of its divisors is an integer number (830599560).

Almost surely, 2^1661199119 is an apocalyptic number.

1661199119 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661199119 is an equidigital number, since it uses as much as digits as its factorization.

1661199119 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26244, while the sum is 44.

The square root of 1661199119 is about 40757.8105275541. The cubic root of 1661199119 is about 1184.3331822608. Note that the first 3 decimals are identical.

The spelling of 1661199119 in words is "one billion, six hundred sixty-one million, one hundred ninety-nine thousand, one hundred nineteen".