7121705 has 4 divisors (see below), whose sum is σ = 8546052. Its totient is φ = 5697360.

The previous prime is 7121701. The next prime is 7121707. The reversal of 7121705 is 5071217.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5071217 = 83 ⋅61099.

It can be written as a sum of positive squares in 2 ways, for example, as 2715904 + 4405801 = 1648^2 + 2099^2 .

It is not a de Polignac number, because 7121705 - 2² = 7121701 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7121701) 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, 712166 + ... + 712175.

It is an arithmetic number, because the mean of its divisors is an integer number (2136513).

Almost surely, 2^7121705 is an apocalyptic number.

It is an amenable number.

7121705 is a deficient number, since it is larger than the sum of its proper divisors (1424347).

7121705 is a wasteful number, since it uses less digits than its factorization.

7121705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1424346.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 7121705 is about 2668.6522815833. The cubic root of 7121705 is about 192.3953892738.

The spelling of 7121705 in words is "seven million, one hundred twenty-one thousand, seven hundred five".