1861864 has 16 divisors (see below), whose sum is σ = 3510720. Its totient is φ = 925680.

The previous prime is 1861861. The next prime is 1861879. The reversal of 1861864 is 4681681.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861861) 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, 1137 + ... + 2239.

It is an arithmetic number, because the mean of its divisors is an integer number (219420).

2^1861864 is an apocalyptic number.

It is an amenable number.

1861864 is a deficient number, since it is larger than the sum of its proper divisors (1648856).

1861864 is a wasteful number, since it uses less digits than its factorization.

1861864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1320 (or 1316 counting only the distinct ones).

The product of its digits is 9216, while the sum is 34.

The square root of 1861864 is about 1364.5013741290. The cubic root of 1861864 is about 123.0219627206.

The spelling of 1861864 in words is "one million, eight hundred sixty-one thousand, eight hundred sixty-four".