140091661 has 2 divisors, whose sum is σ = 140091662. Its totient is φ = 140091660.

The previous prime is 140091649. The next prime is 140091691. The reversal of 140091661 is 166190041.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84290761 + 55800900 = 9181^2 + 7470^2 .

It is a cyclic number.

It is not a de Polignac number, because 140091661 - 2⁷ = 140091533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (140091691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70045830 + 70045831.

It is an arithmetic number, because the mean of its divisors is an integer number (70045831).

Almost surely, 2^140091661 is an apocalyptic number.

It is an amenable number.

140091661 is a deficient number, since it is larger than the sum of its proper divisors (1).

140091661 is an equidigital number, since it uses as much as digits as its factorization.

140091661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 140091661 is about 11836.0323166169. The cubic root of 140091661 is about 519.3627067014.

The spelling of 140091661 in words is "one hundred forty million, ninety-one thousand, six hundred sixty-one".