70306721 has 2 divisors, whose sum is σ = 70306722. Its totient is φ = 70306720.

The previous prime is 70306637. The next prime is 70306757. The reversal of 70306721 is 12760307.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47458321 + 22848400 = 6889^2 + 4780^2 .

It is a cyclic number.

It is not a de Polignac number, because 70306721 - 2¹⁸ = 70044577 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (70306921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35153360 + 35153361.

It is an arithmetic number, because the mean of its divisors is an integer number (35153361).

Almost surely, 2^70306721 is an apocalyptic number.

It is an amenable number.

70306721 is a deficient number, since it is larger than the sum of its proper divisors (1).

70306721 is an equidigital number, since it uses as much as digits as its factorization.

70306721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764, while the sum is 26.

The square root of 70306721 is about 8384.9103155609. The cubic root of 70306721 is about 412.7295980464.

The spelling of 70306721 in words is "seventy million, three hundred six thousand, seven hundred twenty-one".