20173132513 has 4 divisors (see below), whose sum is σ = 20449476868. Its totient is φ = 19896788160.

The previous prime is 20173132481. The next prime is 20173132571. The reversal of 20173132513 is 31523137102.

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 6944222224 + 13228910289 = 83332^2 + 115017^2 .

It is a cyclic number.

It is not a de Polignac number, because 20173132513 - 2⁵ = 20173132481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20173132313) 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, 138172068 + ... + 138172213.

It is an arithmetic number, because the mean of its divisors is an integer number (5112369217).

Almost surely, 2^20173132513 is an apocalyptic number.

It is an amenable number.

20173132513 is a deficient number, since it is larger than the sum of its proper divisors (276344355).

20173132513 is an equidigital number, since it uses as much as digits as its factorization.

20173132513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276344354.

The product of its (nonzero) digits is 3780, while the sum is 28.

Adding to 20173132513 its reverse (31523137102), we get a palindrome (51696269615).

The spelling of 20173132513 in words is "twenty billion, one hundred seventy-three million, one hundred thirty-two thousand, five hundred thirteen".