1581349338 has 64 divisors (see below), whose sum is σ = 3615131520. Its totient is φ = 512096256.

The previous prime is 1581349307. The next prime is 1581349361. The reversal of 1581349338 is 8339431851.

1581349338 is a `hidden beast` number, since 1 + 581 + 34 + 9 + 3 + 38 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1581349293 and 1581349302.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 455706 + ... + 459162.

It is an arithmetic number, because the mean of its divisors is an integer number (56486430).

Almost surely, 2^1581349338 is an apocalyptic number.

1581349338 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1581349338, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1807565760).

1581349338 is an abundant number, since it is smaller than the sum of its proper divisors (2033782182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1581349338 is a wasteful number, since it uses less digits than its factorization.

1581349338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3708 (or 3702 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 1581349338 is about 39766.1833471607. The cubic root of 1581349338 is about 1165.0447496426.

The spelling of 1581349338 in words is "one billion, five hundred eighty-one million, three hundred forty-nine thousand, three hundred thirty-eight".