1581255 has 64 divisors (see below), whose sum is σ = 3265920. Its totient is φ = 718848.

The previous prime is 1581211. The next prime is 1581257. The reversal of 1581255 is 5521851.

It is not a de Polignac number, because 1581255 - 2⁶ = 1581191 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581257) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 29809 + ... + 29861.

It is an arithmetic number, because the mean of its divisors is an integer number (51030).

2^1581255 is an apocalyptic number.

1581255 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1581255 is an abundant number, since it is smaller than the sum of its proper divisors (1684665).

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

1581255 is a wasteful number, since it uses less digits than its factorization.

1581255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 91 counting only the distinct ones).

The product of its digits is 2000, while the sum is 27.

The square root of 1581255 is about 1257.4796221013. The cubic root of 1581255 is about 116.5021581627.

The spelling of 1581255 in words is "one million, five hundred eighty-one thousand, two hundred fifty-five".