40007881 has 2 divisors, whose sum is σ = 40007882. Its totient is φ = 40007880.

The previous prime is 40007843. The next prime is 40007897. The reversal of 40007881 is 18870004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36240400 + 3767481 = 6020^2 + 1941^2 .

It is a cyclic number.

It is not a de Polignac number, because 40007881 - 2¹⁹ = 39483593 is a prime.

It is a super-2 number, since 2×40007881² = 3201261084220322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (40007801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20003940 + 20003941.

It is an arithmetic number, because the mean of its divisors is an integer number (20003941).

Almost surely, 2^40007881 is an apocalyptic number.

It is an amenable number.

40007881 is a deficient number, since it is larger than the sum of its proper divisors (1).

40007881 is an equidigital number, since it uses as much as digits as its factorization.

40007881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 40007881 is about 6325.1783374068. The cubic root of 40007881 is about 342.0176483945.

Adding to 40007881 its reverse (18870004), we get a palindrome (58877885).

It can be divided in two parts, 4000 and 7881, that added together give a square (11881 = 109²).

The spelling of 40007881 in words is "forty million, seven thousand, eight hundred eighty-one".