1611121111 has 8 divisors (see below), whose sum is σ = 1627718144. Its totient is φ = 1594585440.

The previous prime is 1611121103. The next prime is 1611121121. The reversal of 1611121111 is 1111211161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1611121111 - 2³ = 1611121103 is a prime.

It is a super-2 number, since 2×1611121111² = 5191422468619748642, which 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 (1611121121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38401 + ... + 68533.

It is an arithmetic number, because the mean of its divisors is an integer number (203464768).

Almost surely, 2^1611121111 is an apocalyptic number.

1611121111 is a deficient number, since it is larger than the sum of its proper divisors (16597033).

1611121111 is a wasteful number, since it uses less digits than its factorization.

1611121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30681.

The product of its digits is 12, while the sum is 16.

The square root of 1611121111 is about 40138.7731626167. The cubic root of 1611121111 is about 1172.3107014330.

Adding to 1611121111 its reverse (1111211161), we get a palindrome (2722332272).

The spelling of 1611121111 in words is "one billion, six hundred eleven million, one hundred twenty-one thousand, one hundred eleven".