706506721 has 4 divisors (see below), whose sum is σ = 706695444. Its totient is φ = 706318000.

The previous prime is 706506719. The next prime is 706506781. The reversal of 706506721 is 127605607.

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 687488400 + 19018321 = 26220^2 + 4361^2 .

It is a cyclic number.

It is not a de Polignac number, because 706506721 - 2¹ = 706506719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (706506701) 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, 88630 + ... + 96271.

It is an arithmetic number, because the mean of its divisors is an integer number (176673861).

Almost surely, 2^706506721 is an apocalyptic number.

It is an amenable number.

706506721 is a deficient number, since it is larger than the sum of its proper divisors (188723).

706506721 is a wasteful number, since it uses less digits than its factorization.

706506721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188722.

The product of its (nonzero) digits is 17640, while the sum is 34.

The square root of 706506721 is about 26580.1941490276. The cubic root of 706506721 is about 890.6466373338.

The spelling of 706506721 in words is "seven hundred six million, five hundred six thousand, seven hundred twenty-one".