90688973909 has 2 divisors, whose sum is σ = 90688973910. Its totient is φ = 90688973908.

The previous prime is 90688973897. The next prime is 90688973983. The reversal of 90688973909 is 90937988609.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78072742225 + 12616231684 = 279415^2 + 112322^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90688973909 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90688973509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45344486954 + 45344486955.

It is an arithmetic number, because the mean of its divisors is an integer number (45344486955).

Almost surely, 2^90688973909 is an apocalyptic number.

It is an amenable number.

90688973909 is a deficient number, since it is larger than the sum of its proper divisors (1).

90688973909 is an equidigital number, since it uses as much as digits as its factorization.

90688973909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52907904, while the sum is 68.

The spelling of 90688973909 in words is "ninety billion, six hundred eighty-eight million, nine hundred seventy-three thousand, nine hundred nine".