1601521013 has 4 divisors (see below), whose sum is σ = 1601602860. Its totient is φ = 1601439168.

The previous prime is 1601521007. The next prime is 1601521021. The reversal of 1601521013 is 3101251061.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 192044164 + 1409476849 = 13858^2 + 37543^2 .

It is a cyclic number.

It is not a de Polignac number, because 1601521013 - 2¹⁰ = 1601519989 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601521043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7631 + ... + 57107.

It is an arithmetic number, because the mean of its divisors is an integer number (400400715).

Almost surely, 2^1601521013 is an apocalyptic number.

It is an amenable number.

1601521013 is a deficient number, since it is larger than the sum of its proper divisors (81847).

1601521013 is an equidigital number, since it uses as much as digits as its factorization.

1601521013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81846.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 1601521013 is about 40019.0081461298. The cubic root of 1601521013 is about 1169.9776003212.

Adding to 1601521013 its reverse (3101251061), we get a palindrome (4702772074).

The spelling of 1601521013 in words is "one billion, six hundred one million, five hundred twenty-one thousand, thirteen".