1986538 has 4 divisors (see below), whose sum is σ = 2979810. Its totient is φ = 993268.

The previous prime is 1986527. The next prime is 1986539. The reversal of 1986538 is 8356891.

It is a happy number.

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., 1979649 + 6889 = 1407^2 + 83^2 .

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 a self number, because there is not a number n which added to its sum of digits gives 1986538.

It is not an unprimeable number, because it can be changed into a prime (1986539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 496633 + ... + 496636.

2^1986538 is an apocalyptic number.

1986538 is a deficient number, since it is larger than the sum of its proper divisors (993272).

1986538 is an equidigital number, since it uses as much as digits as its factorization.

1986538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993271.

The product of its digits is 51840, while the sum is 40.

The square root of 1986538 is about 1409.4459904516. The cubic root of 1986538 is about 125.7087840715.

The spelling of 1986538 in words is "one million, nine hundred eighty-six thousand, five hundred thirty-eight".