1975989 has 4 divisors (see below), whose sum is σ = 2634656. Its totient is φ = 1317324.

The previous prime is 1975957. The next prime is 1975991. The reversal of 1975989 is 9895791.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9895791 = 3 ⋅3298597.

It is not a de Polignac number, because 1975989 - 2⁵ = 1975957 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1975949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 329329 + ... + 329334.

It is an arithmetic number, because the mean of its divisors is an integer number (658664).

2^1975989 is an apocalyptic number.

It is an amenable number.

1975989 is a deficient number, since it is larger than the sum of its proper divisors (658667).

1975989 is an equidigital number, since it uses as much as digits as its factorization.

1975989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 658666.

The product of its digits is 204120, while the sum is 48.

The square root of 1975989 is about 1405.6987586250. The cubic root of 1975989 is about 125.4858742957.

The spelling of 1975989 in words is "one million, nine hundred seventy-five thousand, nine hundred eighty-nine".