672394721 has 2 divisors, whose sum is σ = 672394722. Its totient is φ = 672394720.

The previous prime is 672394717. The next prime is 672394759. The reversal of 672394721 is 127493276.

672394721 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., 422754721 + 249640000 = 20561^2 + 15800^2 .

It is a cyclic number.

It is not a de Polignac number, because 672394721 - 2² = 672394717 is a prime.

It is a super-2 number, since 2×672394721² = 904229321657335682, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (672394771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336197360 + 336197361.

It is an arithmetic number, because the mean of its divisors is an integer number (336197361).

Almost surely, 2^672394721 is an apocalyptic number.

It is an amenable number.

672394721 is a deficient number, since it is larger than the sum of its proper divisors (1).

672394721 is an equidigital number, since it uses as much as digits as its factorization.

672394721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 41.

The square root of 672394721 is about 25930.5750225482. The cubic root of 672394721 is about 876.0752912532.

The spelling of 672394721 in words is "six hundred seventy-two million, three hundred ninety-four thousand, seven hundred twenty-one".