1386945 has 72 divisors (see below), whose sum is σ = 3041064. Its totient is φ = 580608.

The previous prime is 1386929. The next prime is 1386947. The reversal of 1386945 is 5496831.

1386945 is a nontrivial binomial coefficient, being equal to C(1666, 2).

It can be written as a sum of positive squares in 4 ways, for example, as 571536 + 815409 = 756^2 + 903^2 .

It is not a de Polignac number, because 1386945 - 2⁴ = 1386929 is a prime.

It is a Curzon number.

1386945 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1386947) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 37467 + ... + 37503.

It is an arithmetic number, because the mean of its divisors is an integer number (42237).

2^1386945 is an apocalyptic number.

1386945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1386945 is the 1665-th triangular number and also the 833-rd hexagonal number.

It is an amenable number.

1386945 is an abundant number, since it is smaller than the sum of its proper divisors (1654119).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1386945 is a wasteful number, since it uses less digits than its factorization.

1386945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 69 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 1386945 is about 1177.6862909960. The cubic root of 1386945 is about 111.5200819131.

The spelling of 1386945 in words is "one million, three hundred eighty-six thousand, nine hundred forty-five".