1361989 has 8 divisors (see below), whose sum is σ = 1456920. Its totient is φ = 1268736.

The previous prime is 1361963. The next prime is 1361999. The reversal of 1361989 is 9891631.

It can be written as a sum of positive squares in 4 ways, for example, as 100 + 1361889 = 10^2 + 1167^2 .

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 1361989 - 2⁵ = 1361957 is a prime.

It is a super-2 number, since 2×1361989² = 3710028072242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1567 + ... + 2275.

It is an arithmetic number, because the mean of its divisors is an integer number (182115).

2^1361989 is an apocalyptic number.

It is an amenable number.

1361989 is a deficient number, since it is larger than the sum of its proper divisors (94931).

1361989 is a wasteful number, since it uses less digits than its factorization.

1361989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 839.

The product of its digits is 11664, while the sum is 37.

The square root of 1361989 is about 1167.0428441150. The cubic root of 1361989 is about 110.8471504938.

Adding to 1361989 its product of digits (11664), we get a triangular number (1373653 = T₁₆₅₇).

The spelling of 1361989 in words is "one million, three hundred sixty-one thousand, nine hundred eighty-nine".