20867581868977 has 2 divisors, whose sum is σ = 20867581868978. Its totient is φ = 20867581868976.

The previous prime is 20867581868951. The next prime is 20867581868983. The reversal of 20867581868977 is 77986818576802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19167155436961 + 1700426432016 = 4378031^2 + 1304004^2 .

It is a cyclic number.

It is not a de Polignac number, because 20867581868977 - 2¹⁹ = 20867581344689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20867581868977.

It is not a weakly prime, because it can be changed into another prime (20867581862977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10433790934488 + 10433790934489.

It is an arithmetic number, because the mean of its divisors is an integer number (10433790934489).

Almost surely, 2^{20867581868977} is an apocalyptic number.

It is an amenable number.

20867581868977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20867581868977 is an equidigital number, since it uses as much as digits as its factorization.

20867581868977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4551966720, while the sum is 82.

The spelling of 20867581868977 in words is "twenty trillion, eight hundred sixty-seven billion, five hundred eighty-one million, eight hundred sixty-eight thousand, nine hundred seventy-seven".