90566172779 has 2 divisors, whose sum is σ = 90566172780. Its totient is φ = 90566172778.

The previous prime is 90566172761. The next prime is 90566172839. The reversal of 90566172779 is 97727166509.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90566172779 is a prime.

It is not a weakly prime, because it can be changed into another prime (90566172379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45283086389 + 45283086390.

It is an arithmetic number, because the mean of its divisors is an integer number (45283086390).

Almost surely, 2^90566172779 is an apocalyptic number.

90566172779 is a deficient number, since it is larger than the sum of its proper divisors (1).

90566172779 is an equidigital number, since it uses as much as digits as its factorization.

90566172779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10001880, while the sum is 59.

The spelling of 90566172779 in words is "ninety billion, five hundred sixty-six million, one hundred seventy-two thousand, seven hundred seventy-nine".