3135781 has 4 divisors (see below), whose sum is σ = 3420864. Its totient is φ = 2850700.

The previous prime is 3135773. The next prime is 3135809. The reversal of 3135781 is 1875313.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1875313 = 11 ⋅170483.

It is a cyclic number.

It is not a de Polignac number, because 3135781 - 2³ = 3135773 is a prime.

It is a super-2 number, since 2×3135781² = 19666244959922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3135731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142525 + ... + 142546.

It is an arithmetic number, because the mean of its divisors is an integer number (855216).

Almost surely, 2^3135781 is an apocalyptic number.

It is an amenable number.

3135781 is a deficient number, since it is larger than the sum of its proper divisors (285083).

3135781 is a wasteful number, since it uses less digits than its factorization.

3135781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285082.

The product of its digits is 2520, while the sum is 28.

The square root of 3135781 is about 1770.8136547926. The cubic root of 3135781 is about 146.3688210599.

It can be divided in two parts, 3135 and 781, that added together give a triangular number (3916 = T₈₈).

The spelling of 3135781 in words is "three million, one hundred thirty-five thousand, seven hundred eighty-one".