1205521 has 4 divisors (see below), whose sum is σ = 1276452. Its totient is φ = 1134592.

The previous prime is 1205513. The next prime is 1205527. The reversal of 1205521 is 1255021.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 801025 + 404496 = 895^2 + 636^2 .

It is a cyclic number.

It is not a de Polignac number, because 1205521 - 2³ = 1205513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1205495 and 1205504.

It is not an unprimeable number, because it can be changed into a prime (1205527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35440 + ... + 35473.

It is an arithmetic number, because the mean of its divisors is an integer number (319113).

2^1205521 is an apocalyptic number.

It is an amenable number.

1205521 is a deficient number, since it is larger than the sum of its proper divisors (70931).

1205521 is an equidigital number, since it uses as much as digits as its factorization.

1205521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70930.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 1205521 is about 1097.9622033567. The cubic root of 1205521 is about 106.4285781207.

The spelling of 1205521 in words is "one million, two hundred five thousand, five hundred twenty-one".