40491881 has 2 divisors, whose sum is σ = 40491882. Its totient is φ = 40491880.

The previous prime is 40491833. The next prime is 40491911. The reversal of 40491881 is 18819404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35581225 + 4910656 = 5965^2 + 2216^2 .

It is a cyclic number.

It is not a de Polignac number, because 40491881 - 2⁶ = 40491817 is a prime.

It is a super-2 number, since 2×40491881² = 3279184853836322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (40491811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20245940 + 20245941.

It is an arithmetic number, because the mean of its divisors is an integer number (20245941).

Almost surely, 2^40491881 is an apocalyptic number.

It is an amenable number.

40491881 is a deficient number, since it is larger than the sum of its proper divisors (1).

40491881 is an equidigital number, since it uses as much as digits as its factorization.

40491881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 40491881 is about 6363.3231098224. The cubic root of 40491881 is about 343.3913232449.

The spelling of 40491881 in words is "forty million, four hundred ninety-one thousand, eight hundred eighty-one".