1008505381 has 4 divisors (see below), whose sum is σ = 1086082732. Its totient is φ = 930928032.

The previous prime is 1008505327. The next prime is 1008505397. The reversal of 1008505381 is 1835058001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1835058001 = 7 ⋅262151143.

It can be written as a sum of positive squares in 2 ways, for example, as 80389156 + 928116225 = 8966^2 + 30465^2 .

It is a cyclic number.

It is not a de Polignac number, because 1008505381 - 2¹⁷ = 1008374309 is a prime.

It is a super-2 number, since 2×1008505381² = 2034166207011910322, 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 (1008505181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38788656 + ... + 38788681.

It is an arithmetic number, because the mean of its divisors is an integer number (271520683).

Almost surely, 2^1008505381 is an apocalyptic number.

It is an amenable number.

1008505381 is a deficient number, since it is larger than the sum of its proper divisors (77577351).

1008505381 is an equidigital number, since it uses as much as digits as its factorization.

1008505381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77577350.

The product of its (nonzero) digits is 4800, while the sum is 31.

The square root of 1008505381 is about 31756.9737380626. The cubic root of 1008505381 is about 1002.8271268219.

The spelling of 1008505381 in words is "one billion, eight million, five hundred five thousand, three hundred eighty-one".