1581423541 has 4 divisors (see below), whose sum is σ = 1603697184. Its totient is φ = 1559149900.

The previous prime is 1581423533. The next prime is 1581423583. The reversal of 1581423541 is 1453241851.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1581423541 - 2³ = 1581423533 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1581423497 and 1581423506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581427541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11136715 + ... + 11136856.

It is an arithmetic number, because the mean of its divisors is an integer number (400924296).

Almost surely, 2^1581423541 is an apocalyptic number.

It is an amenable number.

1581423541 is a deficient number, since it is larger than the sum of its proper divisors (22273643).

1581423541 is an equidigital number, since it uses as much as digits as its factorization.

1581423541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22273642.

The product of its digits is 19200, while the sum is 34.

The square root of 1581423541 is about 39767.1163274382. The cubic root of 1581423541 is about 1165.0629721528.

The spelling of 1581423541 in words is "one billion, five hundred eighty-one million, four hundred twenty-three thousand, five hundred forty-one".