1381505885 has 8 divisors (see below), whose sum is σ = 1661862840. Its totient is φ = 1102500864.

The previous prime is 1381505869. The next prime is 1381505887. The reversal of 1381505885 is 5885051831.

It can be written as a sum of positive squares in 4 ways, for example, as 474411961 + 907093924 = 21781^2 + 30118^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1381505885 - 2⁴ = 1381505869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381505887) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335732 + ... + 339821.

It is an arithmetic number, because the mean of its divisors is an integer number (207732855).

Almost surely, 2^1381505885 is an apocalyptic number.

It is an amenable number.

1381505885 is a deficient number, since it is larger than the sum of its proper divisors (280356955).

1381505885 is an equidigital number, since it uses as much as digits as its factorization.

1381505885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 675967.

The product of its (nonzero) digits is 192000, while the sum is 44.

The square root of 1381505885 is about 37168.6142464311. The cubic root of 1381505885 is about 1113.7410996235.

The spelling of 1381505885 in words is "one billion, three hundred eighty-one million, five hundred five thousand, eight hundred eighty-five".