40555135781 has 2 divisors, whose sum is σ = 40555135782. Its totient is φ = 40555135780.

The previous prime is 40555135739. The next prime is 40555135801. The reversal of 40555135781 is 18753155504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27137620225 + 13417515556 = 164735^2 + 115834^2 .

It is a cyclic number.

It is not a de Polignac number, because 40555135781 - 2⁶ = 40555135717 is a prime.

It is a super-2 number, since 2×40555135781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40555135721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20277567890 + 20277567891.

It is an arithmetic number, because the mean of its divisors is an integer number (20277567891).

Almost surely, 2^40555135781 is an apocalyptic number.

It is an amenable number.

40555135781 is a deficient number, since it is larger than the sum of its proper divisors (1).

40555135781 is an equidigital number, since it uses as much as digits as its factorization.

40555135781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420000, while the sum is 44.

The spelling of 40555135781 in words is "forty billion, five hundred fifty-five million, one hundred thirty-five thousand, seven hundred eighty-one".