1986157 has 4 divisors (see below), whose sum is σ = 1990336. Its totient is φ = 1981980.

The previous prime is 1986137. The next prime is 1986167. The reversal of 1986157 is 7516891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1986157 - 2⁷ = 1986029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1986137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1269 + ... + 2362.

It is an arithmetic number, because the mean of its divisors is an integer number (497584).

2^1986157 is an apocalyptic number.

It is an amenable number.

1986157 is a deficient number, since it is larger than the sum of its proper divisors (4179).

1986157 is an equidigital number, since it uses as much as digits as its factorization.

1986157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4178.

The product of its digits is 15120, while the sum is 37.

The square root of 1986157 is about 1409.3108244812. The cubic root of 1986157 is about 125.7007469555.

The spelling of 1986157 in words is "one million, nine hundred eighty-six thousand, one hundred fifty-seven".