1365866 has 4 divisors (see below), whose sum is σ = 2048802. Its totient is φ = 682932.

The previous prime is 1365821. The next prime is 1365869. The reversal of 1365866 is 6685631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6685631 = 29 ⋅230539.

It can be written as a sum of positive squares in only one way, i.e., 970225 + 395641 = 985^2 + 629^2 .

It is not an unprimeable number, because it can be changed into a prime (1365869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 341465 + ... + 341468.

2^1365866 is an apocalyptic number.

1365866 is a deficient number, since it is larger than the sum of its proper divisors (682936).

1365866 is an equidigital number, since it uses as much as digits as its factorization.

1365866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 682935.

The product of its digits is 25920, while the sum is 35.

The square root of 1365866 is about 1168.7026995776. The cubic root of 1365866 is about 110.9522289906.

The spelling of 1365866 in words is "one million, three hundred sixty-five thousand, eight hundred sixty-six".