40045381 has 2 divisors, whose sum is σ = 40045382. Its totient is φ = 40045380.

The previous prime is 40045321. The next prime is 40045393. The reversal of 40045381 is 18354004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36180225 + 3865156 = 6015^2 + 1966^2 .

It is a cyclic number.

It is not a de Polignac number, because 40045381 - 2⁷ = 40045253 is a prime.

It is a super-2 number, since 2×40045381² = 3207265078870322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40045301) 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 as a sum of consecutive naturals, namely, 20022690 + 20022691.

It is an arithmetic number, because the mean of its divisors is an integer number (20022691).

Almost surely, 2^40045381 is an apocalyptic number.

It is an amenable number.

40045381 is a deficient number, since it is larger than the sum of its proper divisors (1).

40045381 is an equidigital number, since it uses as much as digits as its factorization.

40045381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 40045381 is about 6328.1419863970. The cubic root of 40045381 is about 342.1244744860.

Adding to 40045381 its reverse (18354004), we get a palindrome (58399385).

The spelling of 40045381 in words is "forty million, forty-five thousand, three hundred eighty-one".