1986491 has 8 divisors (see below), whose sum is σ = 2192064. Its totient is φ = 1788480.

The previous prime is 1986461. The next prime is 1986497. The reversal of 1986491 is 1946891.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1986491 - 2¹⁸ = 1724347 is a prime.

It is a super-2 number, since 2×1986491² = 7892292986162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1986497) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1331 + ... + 2396.

It is an arithmetic number, because the mean of its divisors is an integer number (274008).

2^1986491 is an apocalyptic number.

1986491 is a deficient number, since it is larger than the sum of its proper divisors (205573).

1986491 is a wasteful number, since it uses less digits than its factorization.

1986491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3781.

The product of its digits is 15552, while the sum is 38.

The square root of 1986491 is about 1409.4293171351. The cubic root of 1986491 is about 125.7077926718.

The spelling of 1986491 in words is "one million, nine hundred eighty-six thousand, four hundred ninety-one".