247272721 has 2 divisors, whose sum is σ = 247272722. Its totient is φ = 247272720.

The previous prime is 247272703. The next prime is 247272743. The reversal of 247272721 is 127272742.

247272721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 152794321 + 94478400 = 12361^2 + 9720^2 .

It is a cyclic number.

It is not a de Polignac number, because 247272721 - 2⁹ = 247272209 is a prime.

It is a super-2 number, since 2×247272721² = 122287597101487682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (247272761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123636360 + 123636361.

It is an arithmetic number, because the mean of its divisors is an integer number (123636361).

Almost surely, 2^247272721 is an apocalyptic number.

It is an amenable number.

247272721 is a deficient number, since it is larger than the sum of its proper divisors (1).

247272721 is an equidigital number, since it uses as much as digits as its factorization.

247272721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21952, while the sum is 34.

The square root of 247272721 is about 15724.9076626860. The cubic root of 247272721 is about 627.6613731829.

The spelling of 247272721 in words is "two hundred forty-seven million, two hundred seventy-two thousand, seven hundred twenty-one".