1371989 has 2 divisors, whose sum is σ = 1371990. Its totient is φ = 1371988.

The previous prime is 1371949. The next prime is 1371991. The reversal of 1371989 is 9891731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1085764 + 286225 = 1042^2 + 535^2 .

It is an emirp because it is prime and its reverse (9891731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1371989 - 2¹² = 1367893 is a prime.

It is a super-2 number, since 2×1371989² = 3764707632242, which contains 22 as substring.

Together with 1371991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1371949) 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 as a sum of consecutive naturals, namely, 685994 + 685995.

It is an arithmetic number, because the mean of its divisors is an integer number (685995).

2^1371989 is an apocalyptic number.

It is an amenable number.

1371989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1371989 is an equidigital number, since it uses as much as digits as its factorization.

1371989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13608, while the sum is 38.

The square root of 1371989 is about 1171.3193415973. The cubic root of 1371989 is about 111.1177766742.

The spelling of 1371989 in words is "one million, three hundred seventy-one thousand, nine hundred eighty-nine".