1380938021 has 4 divisors (see below), whose sum is σ = 1381727532. Its totient is φ = 1380148512.

The previous prime is 1380937969. The next prime is 1380938023. The reversal of 1380938021 is 1208390831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 100300225 + 1280637796 = 10015^2 + 35786^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1380938021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1380938023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 392126 + ... + 395631.

It is an arithmetic number, because the mean of its divisors is an integer number (345431883).

Almost surely, 2^1380938021 is an apocalyptic number.

It is an amenable number.

1380938021 is a deficient number, since it is larger than the sum of its proper divisors (789511).

1380938021 is an equidigital number, since it uses as much as digits as its factorization.

1380938021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789510.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 1380938021 is about 37160.9744355554. The cubic root of 1380938021 is about 1113.5884786904.

The spelling of 1380938021 in words is "one billion, three hundred eighty million, nine hundred thirty-eight thousand, twenty-one".