40573731661 has 2 divisors, whose sum is σ = 40573731662. Its totient is φ = 40573731660.

The previous prime is 40573731623. The next prime is 40573731707. The reversal of 40573731661 is 16613737504.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24664702500 + 15909029161 = 157050^2 + 126131^2 .

It is a cyclic number.

It is not a de Polignac number, because 40573731661 - 2⁷ = 40573731533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40573731361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20286865830 + 20286865831.

It is an arithmetic number, because the mean of its divisors is an integer number (20286865831).

Almost surely, 2^40573731661 is an apocalyptic number.

It is an amenable number.

40573731661 is a deficient number, since it is larger than the sum of its proper divisors (1).

40573731661 is an equidigital number, since it uses as much as digits as its factorization.

40573731661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 317520, while the sum is 43.

The spelling of 40573731661 in words is "forty billion, five hundred seventy-three million, seven hundred thirty-one thousand, six hundred sixty-one".