30172121321 has 2 divisors, whose sum is σ = 30172121322. Its totient is φ = 30172121320.

The previous prime is 30172121297. The next prime is 30172121381. The reversal of 30172121321 is 12312127103.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27461461225 + 2710660096 = 165715^2 + 52064^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30172121321 is a prime.

It is not a weakly prime, because it can be changed into another prime (30172121381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15086060660 + 15086060661.

It is an arithmetic number, because the mean of its divisors is an integer number (15086060661).

Almost surely, 2^30172121321 is an apocalyptic number.

It is an amenable number.

30172121321 is a deficient number, since it is larger than the sum of its proper divisors (1).

30172121321 is an equidigital number, since it uses as much as digits as its factorization.

30172121321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 23.

Adding to 30172121321 its reverse (12312127103), we get a palindrome (42484248424).

The spelling of 30172121321 in words is "thirty billion, one hundred seventy-two million, one hundred twenty-one thousand, three hundred twenty-one".