40165784863991 has 2 divisors, whose sum is σ = 40165784863992. Its totient is φ = 40165784863990.

The previous prime is 40165784863951. The next prime is 40165784864021. The reversal of 40165784863991 is 19936848756104.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 40165784863991 - 2¹⁸ = 40165784601847 is a prime.

It is a super-2 number, since 2×40165784863991² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40165784863921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20082892431995 + 20082892431996.

It is an arithmetic number, because the mean of its divisors is an integer number (20082892431996).

Almost surely, 2^{40165784863991} is an apocalyptic number.

40165784863991 is a deficient number, since it is larger than the sum of its proper divisors (1).

40165784863991 is an equidigital number, since it uses as much as digits as its factorization.

40165784863991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 313528320, while the sum is 71.

The spelling of 40165784863991 in words is "forty trillion, one hundred sixty-five billion, seven hundred eighty-four million, eight hundred sixty-three thousand, nine hundred ninety-one".