1201604521 has 4 divisors (see below), whose sum is σ = 1294035652. Its totient is φ = 1109173392.

The previous prime is 1201604501. The next prime is 1201604567. The reversal of 1201604521 is 1254061021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1254061021 = 229 ⋅5476249.

It can be written as a sum of positive squares in 2 ways, for example, as 394419600 + 807184921 = 19860^2 + 28411^2 .

It is a cyclic number.

It is not a de Polignac number, because 1201604521 - 2¹¹ = 1201602473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1201604492 and 1201604501.

It is not an unprimeable number, because it can be changed into a prime (1201604501) 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, 46215546 + ... + 46215571.

It is an arithmetic number, because the mean of its divisors is an integer number (323508913).

Almost surely, 2^1201604521 is an apocalyptic number.

It is an amenable number.

1201604521 is a deficient number, since it is larger than the sum of its proper divisors (92431131).

1201604521 is an equidigital number, since it uses as much as digits as its factorization.

1201604521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92431130.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 1201604521 is about 34664.1676807622. The cubic root of 1201604521 is about 1063.1319854630.

Adding to 1201604521 its reverse (1254061021), we get a palindrome (2455665542).

The spelling of 1201604521 in words is "one billion, two hundred one million, six hundred four thousand, five hundred twenty-one".