3815581 has 12 divisors (see below), whose sum is σ = 4842720. Its totient is φ = 2972760.

The previous prime is 3815579. The next prime is 3815597. The reversal of 3815581 is 1855183.

It is not a de Polignac number, because 3815581 - 2¹ = 3815579 is a prime.

It is a super-2 number, since 2×3815581² = 29117316735122, which contains 22 as substring.

It is a Duffinian number.

3815581 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3815521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3001 + ... + 4078.

It is an arithmetic number, because the mean of its divisors is an integer number (403560).

Almost surely, 2^3815581 is an apocalyptic number.

It is an amenable number.

3815581 is a deficient number, since it is larger than the sum of its proper divisors (1027139).

3815581 is a wasteful number, since it uses less digits than its factorization.

3815581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7104 (or 7097 counting only the distinct ones).

The product of its digits is 4800, while the sum is 31.

The square root of 3815581 is about 1953.3512228987. The cubic root of 3815581 is about 156.2620649884.

The spelling of 3815581 in words is "three million, eight hundred fifteen thousand, five hundred eighty-one".