2015866 has 4 divisors (see below), whose sum is σ = 3023802. Its totient is φ = 1007932.

The previous prime is 2015863. The next prime is 2015869. The reversal of 2015866 is 6685102.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2015863) and next prime (2015869).

It can be written as a sum of positive squares in only one way, i.e., 1243225 + 772641 = 1115^2 + 879^2 .

It is not an unprimeable number, because it can be changed into a prime (2015861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 503965 + ... + 503968.

2^2015866 is an apocalyptic number.

2015866 is a deficient number, since it is larger than the sum of its proper divisors (1007936).

2015866 is a wasteful number, since it uses less digits than its factorization.

2015866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1007935.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 2015866 is about 1419.8119593805. The cubic root of 2015866 is about 126.3243929752.

The spelling of 2015866 in words is "two million, fifteen thousand, eight hundred sixty-six".