3891861 has 32 divisors (see below), whose sum is σ = 6249600. Its totient is φ = 2384640.

The previous prime is 3891857. The next prime is 3891863. The reversal of 3891861 is 1681983.

It is not a de Polignac number, because 3891861 - 2² = 3891857 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3891863) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27930 + ... + 28068.

It is an arithmetic number, because the mean of its divisors is an integer number (195300).

Almost surely, 2^3891861 is an apocalyptic number.

It is an amenable number.

3891861 is a deficient number, since it is larger than the sum of its proper divisors (2357739).

3891861 is a wasteful number, since it uses less digits than its factorization.

3891861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 220 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 3891861 is about 1972.7800181470. The cubic root of 3891861 is about 157.2965172683.

The spelling of 3891861 in words is "three million, eight hundred ninety-one thousand, eight hundred sixty-one".