1987965 has 24 divisors (see below), whose sum is σ = 3938688. Its totient is φ = 908640.

The previous prime is 1987939. The next prime is 1987969. The reversal of 1987965 is 5697891.

It is not a de Polignac number, because 1987965 - 2⁶ = 1987901 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1987965.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987969) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2841 + ... + 3470.

It is an arithmetic number, because the mean of its divisors is an integer number (164112).

2^1987965 is an apocalyptic number.

1987965 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1987965 is a deficient number, since it is larger than the sum of its proper divisors (1950723).

1987965 is a wasteful number, since it uses less digits than its factorization.

1987965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6329 (or 6326 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 1987965 is about 1409.9521268469. The cubic root of 1987965 is about 125.7388772116.

The spelling of 1987965 in words is "one million, nine hundred eighty-seven thousand, nine hundred sixty-five".