1381821831 has 24 divisors (see below), whose sum is σ = 2185943760. Its totient is φ = 835934976.

The previous prime is 1381821823. The next prime is 1381821877. The reversal of 1381821831 is 1381281831.

It is not a de Polignac number, because 1381821831 - 2³ = 1381821823 is a prime.

It is a super-2 number, since 2×1381821831² = 3818863145256385122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381821821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 93186 + ... + 106991.

It is an arithmetic number, because the mean of its divisors is an integer number (91080990).

Almost surely, 2^1381821831 is an apocalyptic number.

1381821831 is a deficient number, since it is larger than the sum of its proper divisors (804121929).

1381821831 is a wasteful number, since it uses less digits than its factorization.

1381821831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200255 (or 200252 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 1381821831 is about 37172.8641753632. The cubic root of 1381821831 is about 1113.8259961672.

The spelling of 1381821831 in words is "one billion, three hundred eighty-one million, eight hundred twenty-one thousand, eight hundred thirty-one".