40111661 has 4 divisors (see below), whose sum is σ = 40165824. Its totient is φ = 40057500.

The previous prime is 40111651. The next prime is 40111739. The reversal of 40111661 is 16611104.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40111661 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 (40111601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25955 + ... + 27456.

It is an arithmetic number, because the mean of its divisors is an integer number (10041456).

Almost surely, 2^40111661 is an apocalyptic number.

It is an amenable number.

40111661 is a deficient number, since it is larger than the sum of its proper divisors (54163).

40111661 is an equidigital number, since it uses as much as digits as its factorization.

40111661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54162.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 40111661 is about 6333.3767454652. The cubic root of 40111661 is about 342.3131230523.

Adding to 40111661 its reverse (16611104), we get a palindrome (56722765).

The spelling of 40111661 in words is "forty million, one hundred eleven thousand, six hundred sixty-one".