20513357317237 has 4 divisors (see below), whose sum is σ = 20555136049536. Its totient is φ = 20471578584940.

The previous prime is 20513357317231. The next prime is 20513357317289. The reversal of 20513357317237 is 73271375331502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20513357317237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20513357317231) 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, 20889365413 + ... + 20889366394.

It is an arithmetic number, because the mean of its divisors is an integer number (5138784012384).

Almost surely, 2^{20513357317237} is an apocalyptic number.

It is an amenable number.

20513357317237 is a deficient number, since it is larger than the sum of its proper divisors (41778732299).

20513357317237 is an equidigital number, since it uses as much as digits as its factorization.

20513357317237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41778732298.

The product of its (nonzero) digits is 2778300, while the sum is 49.

The spelling of 20513357317237 in words is "twenty trillion, five hundred thirteen billion, three hundred fifty-seven million, three hundred seventeen thousand, two hundred thirty-seven".