2591986 has 4 divisors (see below), whose sum is σ = 3887982. Its totient is φ = 1295992.

The previous prime is 2591971. The next prime is 2591987. The reversal of 2591986 is 6891952.

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

It can be written as a sum of positive squares in only one way, i.e., 2544025 + 47961 = 1595^2 + 219^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (2591987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 647995 + ... + 647998.

2^2591986 is an apocalyptic number.

2591986 is a deficient number, since it is larger than the sum of its proper divisors (1295996).

2591986 is a wasteful number, since it uses less digits than its factorization.

2591986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1295995.

The product of its digits is 38880, while the sum is 40.

The square root of 2591986 is about 1609.9645958840. The cubic root of 2591986 is about 137.3654617911.

The spelling of 2591986 in words is "two million, five hundred ninety-one thousand, nine hundred eighty-six".