861240 has 32 divisors (see below), whose sum is σ = 2584080. Its totient is φ = 229632.

The previous prime is 861239. The next prime is 861293. The reversal of 861240 is 42168.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3469 + ... + 3708.

2⁸⁶¹²⁴⁰ is an apocalyptic number.

It is an amenable number.

861240 is an abundant number, since it is smaller than the sum of its proper divisors (1722840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861240 is a wasteful number, since it uses less digits than its factorization.

861240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7191 (or 7187 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 861240 is about 928.0301719233. The cubic root of 861240 is about 95.1425376460.

It can be divided in two parts, 86 and 1240, that added together give a triangular number (1326 = T₅₁).

The spelling of 861240 in words is "eight hundred sixty-one thousand, two hundred forty".