920881609 has 2 divisors, whose sum is σ = 920881610. Its totient is φ = 920881608.

The previous prime is 920881603. The next prime is 920881639. The reversal of 920881609 is 906188029.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 918999225 + 1882384 = 30315^2 + 1372^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-920881609 is a prime.

It is not a weakly prime, because it can be changed into another prime (920881603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460440804 + 460440805.

It is an arithmetic number, because the mean of its divisors is an integer number (460440805).

Almost surely, 2^920881609 is an apocalyptic number.

It is an amenable number.

920881609 is a deficient number, since it is larger than the sum of its proper divisors (1).

920881609 is an equidigital number, since it uses as much as digits as its factorization.

920881609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 920881609 is about 30346.0311902562. The cubic root of 920881609 is about 972.8993948133.

The spelling of 920881609 in words is "nine hundred twenty million, eight hundred eighty-one thousand, six hundred nine".