1581031116 has 96 divisors (see below), whose sum is σ = 4931136000. Its totient is φ = 427944384.

The previous prime is 1581031087. The next prime is 1581031163. The reversal of 1581031116 is 6111301851.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 1581031116.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 40671 + ... + 69398.

It is an arithmetic number, because the mean of its divisors is an integer number (51366000).

Almost surely, 2^1581031116 is an apocalyptic number.

It is an amenable number.

1581031116 is an abundant number, since it is smaller than the sum of its proper divisors (3350104884).

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

1581031116 is a wasteful number, since it uses less digits than its factorization.

1581031116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110108 (or 110100 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 1581031116 is about 39762.1819823812. The cubic root of 1581031116 is about 1164.9665953447.

Adding to 1581031116 its reverse (6111301851), we get a palindrome (7692332967).

The spelling of 1581031116 in words is "one billion, five hundred eighty-one million, thirty-one thousand, one hundred sixteen".