709709981 has 4 divisors (see below), whose sum is σ = 710538972. Its totient is φ = 708880992.

The previous prime is 709709951. The next prime is 709709989. The reversal of 709709981 is 189907907.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 297010756 + 412699225 = 17234^2 + 20315^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-709709981 is a prime.

It is a super-2 number, since 2×709709981² = 1007376514262040722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (709709989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 413210 + ... + 414923.

It is an arithmetic number, because the mean of its divisors is an integer number (177634743).

Almost surely, 2^709709981 is an apocalyptic number.

It is an amenable number.

709709981 is a deficient number, since it is larger than the sum of its proper divisors (828991).

709709981 is an equidigital number, since it uses as much as digits as its factorization.

709709981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828990.

The product of its (nonzero) digits is 285768, while the sum is 50.

The square root of 709709981 is about 26640.3825235300. The cubic root of 709709981 is about 891.9906546676.

The spelling of 709709981 in words is "seven hundred nine million, seven hundred nine thousand, nine hundred eighty-one".