38402809 has 3 divisors (see below), whose sum is σ = 38409007. Its totient is φ = 38396612.

The previous prime is 38402797. The next prime is 38402843. The reversal of 38402809 is 90820483.

The square root of 38402809 is 6197.

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.

It can be written as a sum of positive squares in only one way, i.e., 15093225 + 23309584 = 3885^2 + 4828^2 .

It is not a de Polignac number, because 38402809 - 2⁷ = 38402681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38402849) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 3099 + ... + 9295.

Almost surely, 2^38402809 is an apocalyptic number.

38402809 is the 6197-th square number.

38402809 is the 3099-th centered octagonal number.

It is an amenable number.

38402809 is a deficient number, since it is larger than the sum of its proper divisors (6198).

38402809 is an frugal number, since it uses more digits than its factorization.

38402809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12394 (or 6197 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The cubic root of 38402809 is about 337.3812923172.

The spelling of 38402809 in words is "thirty-eight million, four hundred two thousand, eight hundred nine".