695128121 has 4 divisors (see below), whose sum is σ = 695402532. Its totient is φ = 694853712.

The previous prime is 695128111. The next prime is 695128163. The reversal of 695128121 is 121821596.

695128121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 124634896 + 570493225 = 11164^2 + 23885^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-695128121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (695128111) 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, 133370 + ... + 138483.

It is an arithmetic number, because the mean of its divisors is an integer number (173850633).

Almost surely, 2^695128121 is an apocalyptic number.

It is an amenable number.

695128121 is a deficient number, since it is larger than the sum of its proper divisors (274411).

695128121 is a wasteful number, since it uses less digits than its factorization.

695128121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274410.

The product of its digits is 8640, while the sum is 35.

The square root of 695128121 is about 26365.2824942196. The cubic root of 695128121 is about 885.8393182378.

The spelling of 695128121 in words is "six hundred ninety-five million, one hundred twenty-eight thousand, one hundred twenty-one".