1661035111 has 4 divisors (see below), whose sum is σ = 1661158800. Its totient is φ = 1660911424.

The previous prime is 1661035109. The next prime is 1661035121. The reversal of 1661035111 is 1115301661.

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

It is a cyclic number.

It is not a de Polignac number, because 1661035111 - 2¹ = 1661035109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661035121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38851 + ... + 69508.

It is an arithmetic number, because the mean of its divisors is an integer number (415289700).

Almost surely, 2^1661035111 is an apocalyptic number.

1661035111 is a deficient number, since it is larger than the sum of its proper divisors (123689).

1661035111 is a wasteful number, since it uses less digits than its factorization.

1661035111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123688.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 1661035111 is about 40755.7984954288. The cubic root of 1661035111 is about 1184.2942050932.

Adding to 1661035111 its reverse (1115301661), we get a palindrome (2776336772).

The spelling of 1661035111 in words is "one billion, six hundred sixty-one million, thirty-five thousand, one hundred eleven".