1987313 has 2 divisors, whose sum is σ = 1987314. Its totient is φ = 1987312.

The previous prime is 1987309. The next prime is 1987333. The reversal of 1987313 is 3137891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1763584 + 223729 = 1328^2 + 473^2 .

It is a cyclic number.

It is not a de Polignac number, because 1987313 - 2² = 1987309 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1987313.

It is not a weakly prime, because it can be changed into another prime (1987303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993656 + 993657.

It is an arithmetic number, because the mean of its divisors is an integer number (993657).

2^1987313 is an apocalyptic number.

It is an amenable number.

1987313 is a deficient number, since it is larger than the sum of its proper divisors (1).

1987313 is an equidigital number, since it uses as much as digits as its factorization.

1987313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 32.

The square root of 1987313 is about 1409.7208943617. The cubic root of 1987313 is about 125.7251293652.

The spelling of 1987313 in words is "one million, nine hundred eighty-seven thousand, three hundred thirteen".