1581491412 has 48 divisors (see below), whose sum is σ = 4232435200. Its totient is φ = 510157440.

The previous prime is 1581491399. The next prime is 1581491413. The reversal of 1581491412 is 2141941851.

1581491412 is a `hidden beast` number, since 158 + 1 + 4 + 91 + 412 = 666.

It is a super-2 number, since 2×1581491412² = 5002230172459507488, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581491413) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 232837 + ... + 239532.

Almost surely, 2^1581491412 is an apocalyptic number.

1581491412 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1581491412 is an abundant number, since it is smaller than the sum of its proper divisors (2650943788).

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

1581491412 is a wasteful number, since it uses less digits than its factorization.

1581491412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472413 (or 472405 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 1581491412 is about 39767.9696740983. The cubic root of 1581491412 is about 1165.0796391738.

The spelling of 1581491412 in words is "one billion, five hundred eighty-one million, four hundred ninety-one thousand, four hundred twelve".