1381881881 has 2 divisors, whose sum is σ = 1381881882. Its totient is φ = 1381881880.

The previous prime is 1381881863. The next prime is 1381881911. The reversal of 1381881881 is 1881881831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 893471881 + 488410000 = 29891^2 + 22100^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1381881881 is a prime.

It is a super-2 number, since 2×1381881881² = 3819195066072196322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1381581881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690940940 + 690940941.

It is an arithmetic number, because the mean of its divisors is an integer number (690940941).

Almost surely, 2^1381881881 is an apocalyptic number.

It is an amenable number.

1381881881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1381881881 is an equidigital number, since it uses as much as digits as its factorization.

1381881881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 98304, while the sum is 47.

The square root of 1381881881 is about 37173.6718794364. The cubic root of 1381881881 is about 1113.8421304909.

The spelling of 1381881881 in words is "one billion, three hundred eighty-one million, eight hundred eighty-one thousand, eight hundred eighty-one".