3781309 has 4 divisors (see below), whose sum is σ = 4321504. Its totient is φ = 3241116.

The previous prime is 3781303. The next prime is 3781313. The reversal of 3781309 is 9031873.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3781309 - 2³ = 3781301 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 (3781301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270087 + ... + 270100.

It is an arithmetic number, because the mean of its divisors is an integer number (1080376).

Almost surely, 2^3781309 is an apocalyptic number.

It is an amenable number.

3781309 is a deficient number, since it is larger than the sum of its proper divisors (540195).

3781309 is an equidigital number, since it uses as much as digits as its factorization.

3781309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540194.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 3781309 is about 1944.5588188584. The cubic root of 3781309 is about 155.7928023951.

Subtracting from 3781309 its product of nonzero digits (4536), we obtain a palindrome (3776773).

The spelling of 3781309 in words is "three million, seven hundred eighty-one thousand, three hundred nine".