21000032122177 has 2 divisors, whose sum is σ = 21000032122178. Its totient is φ = 21000032122176.

The previous prime is 21000032122163. The next prime is 21000032122207. The reversal of 21000032122177 is 77122123000012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19213222457521 + 1786809664656 = 4383289^2 + 1336716^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000032122177 is a prime.

It is not a weakly prime, because it can be changed into another prime (21000032122477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500016061088 + 10500016061089.

It is an arithmetic number, because the mean of its divisors is an integer number (10500016061089).

Almost surely, 2^{21000032122177} is an apocalyptic number.

It is an amenable number.

21000032122177 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000032122177 is an equidigital number, since it uses as much as digits as its factorization.

21000032122177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352, while the sum is 28.

Adding to 21000032122177 its reverse (77122123000012), we get a palindrome (98122155122189).

The spelling of 21000032122177 in words is "twenty-one trillion, thirty-two million, one hundred twenty-two thousand, one hundred seventy-seven".