40188661 has 2 divisors, whose sum is σ = 40188662. Its totient is φ = 40188660.

The previous prime is 40188641. The next prime is 40188671. The reversal of 40188661 is 16688104.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29495761 + 10692900 = 5431^2 + 3270^2 .

It is a cyclic number.

It is not a de Polignac number, because 40188661 - 2¹⁵ = 40155893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40188641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20094330 + 20094331.

It is an arithmetic number, because the mean of its divisors is an integer number (20094331).

Almost surely, 2^40188661 is an apocalyptic number.

It is an amenable number.

40188661 is a deficient number, since it is larger than the sum of its proper divisors (1).

40188661 is an equidigital number, since it uses as much as digits as its factorization.

40188661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 40188661 is about 6339.4527366327. The cubic root of 40188661 is about 342.5320225090.

The spelling of 40188661 in words is "forty million, one hundred eighty-eight thousand, six hundred sixty-one".