20153261197 has 4 divisors (see below), whose sum is σ = 20281626076. Its totient is φ = 20024896320.

The previous prime is 20153261143. The next prime is 20153261209. The reversal of 20153261197 is 79116235102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13194197956 + 6959063241 = 114866^2 + 83421^2 .

It is a cyclic number.

It is not a de Polignac number, because 20153261197 - 2¹¹ = 20153259149 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 (20153261137) 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, 64182204 + ... + 64182517.

It is an arithmetic number, because the mean of its divisors is an integer number (5070406519).

Almost surely, 2^20153261197 is an apocalyptic number.

It is an amenable number.

20153261197 is a deficient number, since it is larger than the sum of its proper divisors (128364879).

20153261197 is a wasteful number, since it uses less digits than its factorization.

20153261197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128364878.

The product of its (nonzero) digits is 22680, while the sum is 37.

Adding to 20153261197 its reverse (79116235102), we get a palindrome (99269496299).

The spelling of 20153261197 in words is "twenty billion, one hundred fifty-three million, two hundred sixty-one thousand, one hundred ninety-seven".