40661400061 has 2 divisors, whose sum is σ = 40661400062. Its totient is φ = 40661400060.

The previous prime is 40661400041. The next prime is 40661400067. The reversal of 40661400061 is 16000416604.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33854160025 + 6807240036 = 183995^2 + 82506^2 .

It is a cyclic number.

It is not a de Polignac number, because 40661400061 - 2²⁹ = 40124529149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40661400067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20330700030 + 20330700031.

It is an arithmetic number, because the mean of its divisors is an integer number (20330700031).

Almost surely, 2^40661400061 is an apocalyptic number.

It is an amenable number.

40661400061 is a deficient number, since it is larger than the sum of its proper divisors (1).

40661400061 is an equidigital number, since it uses as much as digits as its factorization.

40661400061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 28.

Adding to 40661400061 its reverse (16000416604), we get a palindrome (56661816665).

The spelling of 40661400061 in words is "forty billion, six hundred sixty-one million, four hundred thousand, sixty-one".