1581057 has 6 divisors (see below), whose sum is σ = 2283762. Its totient is φ = 1054032.

The previous prime is 1581053. The next prime is 1581061. The reversal of 1581057 is 7501851.

It is an interprime number because it is at equal distance from previous prime (1581053) and next prime (1581061).

It can be written as a sum of positive squares in only one way, i.e., 1527696 + 53361 = 1236^2 + 231^2 .

It is not a de Polignac number, because 1581057 - 2² = 1581053 is a prime.

1581057 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1581057.

It is not an unprimeable number, because it can be changed into a prime (1581053) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 87828 + ... + 87845.

It is an arithmetic number, because the mean of its divisors is an integer number (380627).

It is a Proth number, since it is equal to 193 ⋅ 2¹³ + 1 and 193 < 2¹³.

2^1581057 is an apocalyptic number.

It is an amenable number.

1581057 is a deficient number, since it is larger than the sum of its proper divisors (702705).

1581057 is a wasteful number, since it uses less digits than its factorization.

1581057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175679 (or 175676 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 27.

The square root of 1581057 is about 1257.4008907266. The cubic root of 1581057 is about 116.4972952763.

The spelling of 1581057 in words is "one million, five hundred eighty-one thousand, fifty-seven".