1581148020 has 24 divisors (see below), whose sum is σ = 4427214624. Its totient is φ = 421639456.

The previous prime is 1581148013. The next prime is 1581148027. The reversal of 1581148020 is 208411851.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1581148013) and next prime (1581148027).

It is a super-2 number, since 2×1581148020² = 5000058122299840800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581148027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13176174 + ... + 13176293.

It is an arithmetic number, because the mean of its divisors is an integer number (184467276).

Almost surely, 2^1581148020 is an apocalyptic number.

1581148020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1581148020 is an abundant number, since it is smaller than the sum of its proper divisors (2846066604).

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

1581148020 is a wasteful number, since it uses less digits than its factorization.

1581148020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26352479 (or 26352477 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 30.

The square root of 1581148020 is about 39763.6519952582. The cubic root of 1581148020 is about 1164.9953078090.

Adding to 1581148020 its reverse (208411851), we get a palindrome (1789559871).

The spelling of 1581148020 in words is "one billion, five hundred eighty-one million, one hundred forty-eight thousand, twenty".