7115121557 has 4 divisors (see below), whose sum is σ = 7231762956. Its totient is φ = 6998480160.

The previous prime is 7115121529. The next prime is 7115121619. The reversal of 7115121557 is 7551215117.

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 3477342961 + 3637778596 = 58969^2 + 60314^2 .

It is a cyclic number.

It is not a de Polignac number, because 7115121557 - 2⁸ = 7115121301 is a prime.

It is a super-2 number, since 2×7115121557² (a number of 21 digits) 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 (7115121257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58320608 + ... + 58320729.

It is an arithmetic number, because the mean of its divisors is an integer number (1807940739).

Almost surely, 2^7115121557 is an apocalyptic number.

It is an amenable number.

7115121557 is a deficient number, since it is larger than the sum of its proper divisors (116641399).

7115121557 is a wasteful number, since it uses less digits than its factorization.

7115121557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116641398.

The product of its digits is 12250, while the sum is 35.

The square root of 7115121557 is about 84351.1799383980. The cubic root of 7115121557 is about 1923.3608631301.

The spelling of 7115121557 in words is "seven billion, one hundred fifteen million, one hundred twenty-one thousand, five hundred fifty-seven".