1561385 has 12 divisors (see below), whose sum is σ = 2179908. Its totient is φ = 1070496.

The previous prime is 1561367. The next prime is 1561393. The reversal of 1561385 is 5831651.

It can be written as a sum of positive squares in 2 ways, for example, as 946729 + 614656 = 973^2 + 784^2 .

It is not a de Polignac number, because 1561385 - 2¹² = 1557289 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2942 + ... + 3431.

It is an arithmetic number, because the mean of its divisors is an integer number (181659).

2^1561385 is an apocalyptic number.

It is an amenable number.

1561385 is a deficient number, since it is larger than the sum of its proper divisors (618523).

1561385 is an equidigital number, since it uses as much as digits as its factorization.

1561385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6392 (or 6385 counting only the distinct ones).

The product of its digits is 3600, while the sum is 29.

The square root of 1561385 is about 1249.5539204052. The cubic root of 1561385 is about 116.0121122905.

The spelling of 1561385 in words is "one million, five hundred sixty-one thousand, three hundred eighty-five".