20502535231 has 4 divisors (see below), whose sum is σ = 20783391952. Its totient is φ = 20221678512.

The previous prime is 20502535187. The next prime is 20502535241. The reversal of 20502535231 is 13253520502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13253520502 = 2 ⋅6626760251.

It is a cyclic number.

It is not a de Polignac number, because 20502535231 - 2¹⁹ = 20502010943 is a prime.

It is a super-2 number, since 2×20502535231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20502535231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20502535241) 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, 140428251 + ... + 140428396.

It is an arithmetic number, because the mean of its divisors is an integer number (5195847988).

Almost surely, 2^20502535231 is an apocalyptic number.

20502535231 is a deficient number, since it is larger than the sum of its proper divisors (280856721).

20502535231 is an equidigital number, since it uses as much as digits as its factorization.

20502535231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280856720.

The product of its (nonzero) digits is 9000, while the sum is 28.

The spelling of 20502535231 in words is "twenty billion, five hundred two million, five hundred thirty-five thousand, two hundred thirty-one".