706172021 has 2 divisors, whose sum is σ = 706172022. Its totient is φ = 706172020.

The previous prime is 706172009. The next prime is 706172023. The reversal of 706172021 is 120271607.

706172021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 539400625 + 166771396 = 23225^2 + 12914^2 .

It is an emirp because it is prime and its reverse (120271607) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-706172021 is a prime.

Together with 706172023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (706172023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 353086010 + 353086011.

It is an arithmetic number, because the mean of its divisors is an integer number (353086011).

Almost surely, 2^706172021 is an apocalyptic number.

It is an amenable number.

706172021 is a deficient number, since it is larger than the sum of its proper divisors (1).

706172021 is an equidigital number, since it uses as much as digits as its factorization.

706172021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1176, while the sum is 26.

The square root of 706172021 is about 26573.8973618850. The cubic root of 706172021 is about 890.5059703465.

The spelling of 706172021 in words is "seven hundred six million, one hundred seventy-two thousand, twenty-one".