30475721055821 has 2 divisors, whose sum is σ = 30475721055822. Its totient is φ = 30475721055820.

The previous prime is 30475721055749. The next prime is 30475721055823. The reversal of 30475721055821 is 12855012757403.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29302073833321 + 1173647222500 = 5413139^2 + 1083350^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30475721055821 is a prime.

It is a super-2 number, since 2×30475721055821² (a number of 28 digits) contains 22 as substring.

Together with 30475721055823, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30475721055821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30475721055823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15237860527910 + 15237860527911.

It is an arithmetic number, because the mean of its divisors is an integer number (15237860527911).

Almost surely, 2^{30475721055821} is an apocalyptic number.

It is an amenable number.

30475721055821 is a deficient number, since it is larger than the sum of its proper divisors (1).

30475721055821 is an equidigital number, since it uses as much as digits as its factorization.

30475721055821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2352000, while the sum is 50.

The spelling of 30475721055821 in words is "thirty trillion, four hundred seventy-five billion, seven hundred twenty-one million, fifty-five thousand, eight hundred twenty-one".