672102721 has 2 divisors, whose sum is σ = 672102722. Its totient is φ = 672102720.

The previous prime is 672102719. The next prime is 672102763. The reversal of 672102721 is 127201276.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 493506225 + 178596496 = 22215^2 + 13364^2 .

It is a cyclic number.

It is not a de Polignac number, because 672102721 - 2¹ = 672102719 is a prime.

Together with 672102719, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 672102721.

It is not a weakly prime, because it can be changed into another prime (672109721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336051360 + 336051361.

It is an arithmetic number, because the mean of its divisors is an integer number (336051361).

Almost surely, 2^672102721 is an apocalyptic number.

It is an amenable number.

672102721 is a deficient number, since it is larger than the sum of its proper divisors (1).

672102721 is an equidigital number, since it uses as much as digits as its factorization.

672102721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 672102721 is about 25924.9439922249. The cubic root of 672102721 is about 875.9484555238.

Adding to 672102721 its reverse (127201276), we get a palindrome (799303997).

The spelling of 672102721 in words is "six hundred seventy-two million, one hundred two thousand, seven hundred twenty-one".