20613216231 has 10 divisors (see below), whose sum is σ = 30792582392. Its totient is φ = 13742144100.

The previous prime is 20613216191. The next prime is 20613216233. The reversal of 20613216231 is 13261231602.

20613216231 is a `hidden beast` number, since 2 + 0 + 6 + 1 + 32 + 1 + 623 + 1 = 666.

It is not a de Polignac number, because 20613216231 - 2⁷ = 20613216103 is a prime.

It is a super-2 number, since 2×20613216231² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20613216195 and 20613216204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20613216233) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 127241995 + ... + 127242156.

Almost surely, 2^20613216231 is an apocalyptic number.

20613216231 is a deficient number, since it is larger than the sum of its proper divisors (10179366161).

20613216231 is an equidigital number, since it uses as much as digits as its factorization.

20613216231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254484163 (or 254484154 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

Adding to 20613216231 its reverse (13261231602), we get a palindrome (33874447833).

The spelling of 20613216231 in words is "twenty billion, six hundred thirteen million, two hundred sixteen thousand, two hundred thirty-one".