870644 has 6 divisors (see below), whose sum is σ = 1523634. Its totient is φ = 435320.

The previous prime is 870643. The next prime is 870679. The reversal of 870644 is 446078.

870644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 739600 + 131044 = 860^2 + 362^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (870641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108827 + ... + 108834.

It is an arithmetic number, because the mean of its divisors is an integer number (253939).

2⁸⁷⁰⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

870644 is a deficient number, since it is larger than the sum of its proper divisors (652990).

870644 is a wasteful number, since it uses less digits than its factorization.

870644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217665 (or 217663 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 870644 is about 933.0830616831. The cubic root of 870644 is about 95.4875763925.

The spelling of 870644 in words is "eight hundred seventy thousand, six hundred forty-four".