40161691 has 4 divisors (see below), whose sum is σ = 40175352. Its totient is φ = 40148032.

The previous prime is 40161683. The next prime is 40161697. The reversal of 40161691 is 19616104.

40161691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 40161691 - 2³ = 40161683 is a prime.

It is a super-2 number, since 2×40161691² = 3225922847958962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40161697) 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, 406 + ... + 8971.

It is an arithmetic number, because the mean of its divisors is an integer number (10043838).

Almost surely, 2^40161691 is an apocalyptic number.

40161691 is a deficient number, since it is larger than the sum of its proper divisors (13661).

40161691 is an equidigital number, since it uses as much as digits as its factorization.

40161691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13660.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 40161691 is about 6337.3252244145. The cubic root of 40161691 is about 342.4553826832.

Adding to 40161691 its reverse (19616104), we get a palindrome (59777795).

The spelling of 40161691 in words is "forty million, one hundred sixty-one thousand, six hundred ninety-one".