1381731181 has 4 divisors (see below), whose sum is σ = 1383964000. Its totient is φ = 1379498364.

The previous prime is 1381731137. The next prime is 1381731193. The reversal of 1381731181 is 1811371831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1381731181 - 2¹³ = 1381722989 is a prime.

It is a super-2 number, since 2×1381731181² = 3818362113095309522, 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 (1381731581) 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 3 ways as a sum of consecutive naturals, for example, 1115481 + ... + 1116718.

It is an arithmetic number, because the mean of its divisors is an integer number (345991000).

Almost surely, 2^1381731181 is an apocalyptic number.

It is an amenable number.

1381731181 is a deficient number, since it is larger than the sum of its proper divisors (2232819).

1381731181 is an equidigital number, since it uses as much as digits as its factorization.

1381731181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2232818.

The product of its digits is 4032, while the sum is 34.

The square root of 1381731181 is about 37171.6448519567. The cubic root of 1381731181 is about 1113.8016393043.

The spelling of 1381731181 in words is "one billion, three hundred eighty-one million, seven hundred thirty-one thousand, one hundred eighty-one".