1581315120 has 360 divisors, whose sum is σ = 6673718688. Its totient is φ = 328458240.

The previous prime is 1581315119. The next prime is 1581315121. The reversal of 1581315120 is 215131851.

1581315120 is a `hidden beast` number, since 1 + 581 + 31 + 51 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1581315119) and next prime (1581315121).

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-2 number, since 2×1581315120² = 5001115017481228800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1581315121) 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 71 ways as a sum of consecutive naturals, for example, 608544 + ... + 611136.

Almost surely, 2^1581315120 is an apocalyptic number.

1581315120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1581315120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3336859344).

1581315120 is an abundant number, since it is smaller than the sum of its proper divisors (5092403568).

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

1581315120 is a wasteful number, since it uses less digits than its factorization.

1581315120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2641 (or 2621 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 27.

The square root of 1581315120 is about 39765.7531049017. The cubic root of 1581315120 is about 1165.0363463152.

Adding to 1581315120 its reverse (215131851), we get a palindrome (1796446971).

The spelling of 1581315120 in words is "one billion, five hundred eighty-one million, three hundred fifteen thousand, one hundred twenty".