920207309 has 6 divisors (see below), whose sum is σ = 1070445294. Its totient is φ = 788749080.

The previous prime is 920207293. The next prime is 920207311. The reversal of 920207309 is 903702029.

It can be written as a sum of positive squares in only one way, i.e., 690533284 + 229674025 = 26278^2 + 15155^2 .

It is not a de Polignac number, because 920207309 - 2⁴ = 920207293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (920207369) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9389822 + ... + 9389919.

It is an arithmetic number, because the mean of its divisors is an integer number (178407549).

Almost surely, 2^920207309 is an apocalyptic number.

It is an amenable number.

920207309 is a deficient number, since it is larger than the sum of its proper divisors (150237985).

920207309 is a wasteful number, since it uses less digits than its factorization.

920207309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18779755 (or 18779748 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 920207309 is about 30334.9189713769. The cubic root of 920207309 is about 972.6618737820.

The spelling of 920207309 in words is "nine hundred twenty million, two hundred seven thousand, three hundred nine".