30516397721 has 4 divisors (see below), whose sum is σ = 30786454452. Its totient is φ = 30246340992.

The previous prime is 30516397711. The next prime is 30516397727. The reversal of 30516397721 is 12779361503.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3369222025 + 27147175696 = 58045^2 + 164764^2 .

It is a cyclic number.

It is not a de Polignac number, because 30516397721 - 2⁶ = 30516397657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30516397727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135028196 + ... + 135028421.

It is an arithmetic number, because the mean of its divisors is an integer number (7696613613).

Almost surely, 2^30516397721 is an apocalyptic number.

It is an amenable number.

30516397721 is a deficient number, since it is larger than the sum of its proper divisors (270056731).

30516397721 is a wasteful number, since it uses less digits than its factorization.

30516397721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270056730.

The product of its (nonzero) digits is 238140, while the sum is 44.

The spelling of 30516397721 in words is "thirty billion, five hundred sixteen million, three hundred ninety-seven thousand, seven hundred twenty-one".