20506255231 has 8 divisors (see below), whose sum is σ = 25566240384. Its totient is φ = 15978900120.

The previous prime is 20506255183. The next prime is 20506255243. The reversal of 20506255231 is 13255260502.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20506255231 - 2¹³ = 20506247039 is a prime.

It is a super-2 number, since 2×20506255231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20506255193 and 20506255202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20506255031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133157425 + ... + 133157578.

It is an arithmetic number, because the mean of its divisors is an integer number (3195780048).

Almost surely, 2^20506255231 is an apocalyptic number.

20506255231 is a deficient number, since it is larger than the sum of its proper divisors (5059985153).

20506255231 is a wasteful number, since it uses less digits than its factorization.

20506255231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266315021.

The product of its (nonzero) digits is 18000, while the sum is 31.

The spelling of 20506255231 in words is "twenty billion, five hundred six million, two hundred fifty-five thousand, two hundred thirty-one".