40936781 has 2 divisors, whose sum is σ = 40936782. Its totient is φ = 40936780.

The previous prime is 40936747. The next prime is 40936783. The reversal of 40936781 is 18763904.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34515625 + 6421156 = 5875^2 + 2534^2 .

It is a cyclic number.

It is not a de Polignac number, because 40936781 - 2¹⁸ = 40674637 is a prime.

It is a super-2 number, since 2×40936781² = 3351640077283922, which contains 22 as substring.

Together with 40936783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40936783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20468390 + 20468391.

It is an arithmetic number, because the mean of its divisors is an integer number (20468391).

Almost surely, 2^40936781 is an apocalyptic number.

It is an amenable number.

40936781 is a deficient number, since it is larger than the sum of its proper divisors (1).

40936781 is an equidigital number, since it uses as much as digits as its factorization.

40936781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 40936781 is about 6398.1857584787. The cubic root of 40936781 is about 344.6444029124.

The spelling of 40936781 in words is "forty million, nine hundred thirty-six thousand, seven hundred eighty-one".