117155305721 has 8 divisors (see below), whose sum is σ = 121074816744. Its totient is φ = 113286369280.

The previous prime is 117155305717. The next prime is 117155305723. The reversal of 117155305721 is 127503551711.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 20938090000 + 96217215721 = 144700^2 + 310189^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 117155305721 - 2² = 117155305717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (117155305723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12638936 + ... + 12648201.

It is an arithmetic number, because the mean of its divisors is an integer number (15134352093).

Almost surely, 2^117155305721 is an apocalyptic number.

It is an amenable number.

117155305721 is a deficient number, since it is larger than the sum of its proper divisors (3919511023).

117155305721 is a wasteful number, since it uses less digits than its factorization.

117155305721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25287291.

The product of its (nonzero) digits is 36750, while the sum is 38.

The spelling of 117155305721 in words is "one hundred seventeen billion, one hundred fifty-five million, three hundred five thousand, seven hundred twenty-one".