1581491152 has 20 divisors (see below), whose sum is σ = 3135399520. Its totient is φ = 772355808.

The previous prime is 1581491129. The next prime is 1581491167. The reversal of 1581491152 is 2511941851.

It is a happy number.

It is a super-2 number, since 2×1581491152² = 5002228527708574208, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1148652 + ... + 1150027.

It is an arithmetic number, because the mean of its divisors is an integer number (156769976).

Almost surely, 2^1581491152 is an apocalyptic number.

It is an amenable number.

1581491152 is a deficient number, since it is larger than the sum of its proper divisors (1553908368).

1581491152 is a wasteful number, since it uses less digits than its factorization.

1581491152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2298730 (or 2298724 counting only the distinct ones).

The product of its digits is 14400, while the sum is 37.

The square root of 1581491152 is about 39767.9664051357. The cubic root of 1581491152 is about 1165.0795753267.

The spelling of 1581491152 in words is "one billion, five hundred eighty-one million, four hundred ninety-one thousand, one hundred fifty-two".