3155861 has 4 divisors (see below), whose sum is σ = 3167532. Its totient is φ = 3144192.

The previous prime is 3155839. The next prime is 3155923. The reversal of 3155861 is 1685513.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1685513 = 821 ⋅2053.

It can be written as a sum of positive squares in 2 ways, for example, as 1416100 + 1739761 = 1190^2 + 1319^2 .

It is a cyclic number.

It is not a de Polignac number, because 3155861 - 2¹⁸ = 2893717 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 (3155821) 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, 5420 + ... + 5973.

It is an arithmetic number, because the mean of its divisors is an integer number (791883).

Almost surely, 2^3155861 is an apocalyptic number.

It is an amenable number.

3155861 is a deficient number, since it is larger than the sum of its proper divisors (11671).

3155861 is a wasteful number, since it uses less digits than its factorization.

3155861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11670.

The product of its digits is 3600, while the sum is 29.

The square root of 3155861 is about 1776.4743172925. The cubic root of 3155861 is about 146.6805812097.

The spelling of 3155861 in words is "three million, one hundred fifty-five thousand, eight hundred sixty-one".