40531691 has 2 divisors, whose sum is σ = 40531692. Its totient is φ = 40531690.

The previous prime is 40531619. The next prime is 40531753. The reversal of 40531691 is 19613504.

Together with previous prime (40531619) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 40531691 - 2¹⁸ = 40269547 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (40531891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20265845 + 20265846.

It is an arithmetic number, because the mean of its divisors is an integer number (20265846).

Almost surely, 2^40531691 is an apocalyptic number.

40531691 is a deficient number, since it is larger than the sum of its proper divisors (1).

40531691 is an equidigital number, since it uses as much as digits as its factorization.

40531691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 40531691 is about 6366.4504239018. The cubic root of 40531691 is about 343.5038225955.

The spelling of 40531691 in words is "forty million, five hundred thirty-one thousand, six hundred ninety-one".