20555202197 has 8 divisors (see below), whose sum is σ = 21988708056. Its totient is φ = 19146627072.

The previous prime is 20555202149. The next prime is 20555202211. The reversal of 20555202197 is 79120255502.

It can be written as a sum of positive squares in 4 ways, for example, as 1369074001 + 19186128196 = 37001^2 + 138514^2 .

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 20555202197 - 2¹² = 20555198101 is a prime.

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 20555202197.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20555202397) 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, 6230978 + ... + 6234275.

It is an arithmetic number, because the mean of its divisors is an integer number (2748588507).

Almost surely, 2^20555202197 is an apocalyptic number.

It is an amenable number.

20555202197 is a deficient number, since it is larger than the sum of its proper divisors (1433505859).

20555202197 is a wasteful number, since it uses less digits than its factorization.

20555202197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12465367.

The product of its (nonzero) digits is 63000, while the sum is 38.

Adding to 20555202197 its reverse (79120255502), we get a palindrome (99675457699).

The spelling of 20555202197 in words is "twenty billion, five hundred fifty-five million, two hundred two thousand, one hundred ninety-seven".