3161581 has 4 divisors (see below), whose sum is σ = 3328000. Its totient is φ = 2995164.

The previous prime is 3161579. The next prime is 3161593. The reversal of 3161581 is 1851613.

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: 1851613 = 683 ⋅2711.

It is a cyclic number.

It is not a de Polignac number, because 3161581 - 2¹ = 3161579 is a prime.

It is a super-2 number, since 2×3161581² = 19991188839122, 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 (3161681) 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, 83181 + ... + 83218.

It is an arithmetic number, because the mean of its divisors is an integer number (832000).

Almost surely, 2^3161581 is an apocalyptic number.

It is an amenable number.

3161581 is a deficient number, since it is larger than the sum of its proper divisors (166419).

3161581 is a wasteful number, since it uses less digits than its factorization.

3161581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166418.

The product of its digits is 720, while the sum is 25.

The square root of 3161581 is about 1778.0835188483. The cubic root of 3161581 is about 146.7691472704.

The spelling of 3161581 in words is "three million, one hundred sixty-one thousand, five hundred eighty-one".