1864 has 8 divisors (see below), whose sum is σ = 3510. Its totient is φ = 928.

The previous prime is 1861. The next prime is 1867. The reversal of 1864 is 4681.

It is an interprime number because it is at equal distance from previous prime (1861) and next prime (1867).

It can be written as a sum of positive squares in only one way, i.e., 1764 + 100 = 42^2 + 10^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 6 and base 11.

It is a nialpdrome in base 14 and base 15.

It is not an unprimeable number, because it can be changed into a prime (1861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109 + ... + 124.

2¹⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

1864 is a deficient number, since it is larger than the sum of its proper divisors (1646).

1864 is a wasteful number, since it uses less digits than its factorization.

1864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239 (or 235 counting only the distinct ones).

The product of its digits is 192, while the sum is 19.

The square root of 1864 is about 43.1740662898. The cubic root of 1864 is about 12.3068989873.

It can be divided in two parts, 186 and 4, that added together give a triangular number (190 = T₁₉).

The spelling of 1864 in words is "one thousand, eight hundred sixty-four".