40900781 has 2 divisors, whose sum is σ = 40900782. Its totient is φ = 40900780.

The previous prime is 40900771. The next prime is 40900807. The reversal of 40900781 is 18700904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27144100 + 13756681 = 5210^2 + 3709^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40900781 is a prime.

It is a super-2 number, since 2×40900781² = 3345747772819922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40900721) 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, 20450390 + 20450391.

It is an arithmetic number, because the mean of its divisors is an integer number (20450391).

Almost surely, 2^40900781 is an apocalyptic number.

It is an amenable number.

40900781 is a deficient number, since it is larger than the sum of its proper divisors (1).

40900781 is an equidigital number, since it uses as much as digits as its factorization.

40900781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 40900781 is about 6395.3718421996. The cubic root of 40900781 is about 344.5433459740.

The spelling of 40900781 in words is "forty million, nine hundred thousand, seven hundred eighty-one".