90661008640087 has 2 divisors, whose sum is σ = 90661008640088. Its totient is φ = 90661008640086.

The previous prime is 90661008640057. The next prime is 90661008640171. The reversal of 90661008640087 is 78004680016609.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90661008640087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90661008640057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45330504320043 + 45330504320044.

It is an arithmetic number, because the mean of its divisors is an integer number (45330504320044).

Almost surely, 2^{90661008640087} is an apocalyptic number.

90661008640087 is a deficient number, since it is larger than the sum of its proper divisors (1).

90661008640087 is an equidigital number, since it uses as much as digits as its factorization.

90661008640087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3483648, while the sum is 55.

The spelling of 90661008640087 in words is "ninety trillion, six hundred sixty-one billion, eight million, six hundred forty thousand, eighty-seven".