20736613181 has 2 divisors, whose sum is σ = 20736613182. Its totient is φ = 20736613180.

The previous prime is 20736613169. The next prime is 20736613187. The reversal of 20736613181 is 18131663702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20394696100 + 341917081 = 142810^2 + 18491^2 .

It is a cyclic number.

It is not a de Polignac number, because 20736613181 - 2¹⁰ = 20736612157 is a prime.

It is a super-2 number, since 2×20736613181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20736613187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10368306590 + 10368306591.

It is an arithmetic number, because the mean of its divisors is an integer number (10368306591).

Almost surely, 2^20736613181 is an apocalyptic number.

It is an amenable number.

20736613181 is a deficient number, since it is larger than the sum of its proper divisors (1).

20736613181 is an equidigital number, since it uses as much as digits as its factorization.

20736613181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 38.

The spelling of 20736613181 in words is "twenty billion, seven hundred thirty-six million, six hundred thirteen thousand, one hundred eighty-one".