28315961809 has 2 divisors, whose sum is σ = 28315961810. Its totient is φ = 28315961808.

The previous prime is 28315961803. The next prime is 28315961857. The reversal of 28315961809 is 90816951382.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28259291025 + 56670784 = 168105^2 + 7528^2 .

It is a cyclic number.

It is not a de Polignac number, because 28315961809 - 2¹⁵ = 28315929041 is a prime.

It is not a weakly prime, because it can be changed into another prime (28315961803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14157980904 + 14157980905.

It is an arithmetic number, because the mean of its divisors is an integer number (14157980905).

Almost surely, 2^28315961809 is an apocalyptic number.

It is an amenable number.

28315961809 is a deficient number, since it is larger than the sum of its proper divisors (1).

28315961809 is an equidigital number, since it uses as much as digits as its factorization.

28315961809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 933120, while the sum is 52.

The spelling of 28315961809 in words is "twenty-eight billion, three hundred fifteen million, nine hundred sixty-one thousand, eight hundred nine".