321987 has 8 divisors (see below), whose sum is σ = 444240. Its totient is φ = 207200.

The previous prime is 321983. The next prime is 321991. The reversal of 321987 is 789123.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (321983) and next prime (321991).

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 321987 - 2² = 321983 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 321987.

It is not an unprimeable number, because it can be changed into a prime (321983) by changing a digit.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1764 + ... + 1937.

It is an arithmetic number, because the mean of its divisors is an integer number (55530).

2³²¹⁹⁸⁷ is an apocalyptic number.

321987 is a deficient number, since it is larger than the sum of its proper divisors (122253).

321987 is a wasteful number, since it uses less digits than its factorization.

321987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733.

The product of its digits is 3024, while the sum is 30.

The square root of 321987 is about 567.4389835040. The cubic root of 321987 is about 68.5403176083.

The spelling of 321987 in words is "three hundred twenty-one thousand, nine hundred eighty-seven".