40518661 has 2 divisors, whose sum is σ = 40518662. Its totient is φ = 40518660.

The previous prime is 40518637. The next prime is 40518689. The reversal of 40518661 is 16681504.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20884900 + 19633761 = 4570^2 + 4431^2 .

It is a cyclic number.

It is not a de Polignac number, because 40518661 - 2¹¹ = 40516613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40518601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20259330 + 20259331.

It is an arithmetic number, because the mean of its divisors is an integer number (20259331).

Almost surely, 2^40518661 is an apocalyptic number.

It is an amenable number.

40518661 is a deficient number, since it is larger than the sum of its proper divisors (1).

40518661 is an equidigital number, since it uses as much as digits as its factorization.

40518661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 40518661 is about 6365.4270084575. The cubic root of 40518661 is about 343.4670091424.

The spelling of 40518661 in words is "forty million, five hundred eighteen thousand, six hundred sixty-one".