920940409 has 3 divisors (see below), whose sum is σ = 920970757. Its totient is φ = 920910062.

The previous prime is 920940403. The next prime is 920940413. The reversal of 920940409 is 904049029.

The square root of 920940409 is 30347.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 904049029 = 13 ⋅69542233.

It is not a de Polignac number, because 920940409 - 2⁹ = 920939897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (920940403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 15174 + ... + 45520.

Almost surely, 2^920940409 is an apocalyptic number.

920940409 is the 30347-th square number.

920940409 is the 15174-th centered octagonal number.

It is an amenable number.

920940409 is a deficient number, since it is larger than the sum of its proper divisors (30348).

920940409 is an frugal number, since it uses more digits than its factorization.

920940409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60694 (or 30347 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The cubic root of 920940409 is about 972.9201015167.

The spelling of 920940409 in words is "nine hundred twenty million, nine hundred forty thousand, four hundred nine".