15115593478721 has 8 divisors (see below), whose sum is σ = 15502785372864. Its totient is φ = 14732179066800.

The previous prime is 15115593478717. The next prime is 15115593478763. The reversal of 15115593478721 is 12787439551151.

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 15115593478721 - 2² = 15115593478717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15115593478781) 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, 944362451 + ... + 944378456.

It is an arithmetic number, because the mean of its divisors is an integer number (1937848171608).

Almost surely, 2^{15115593478721} is an apocalyptic number.

It is an amenable number.

15115593478721 is a deficient number, since it is larger than the sum of its proper divisors (387191894143).

15115593478721 is a wasteful number, since it uses less digits than its factorization.

15115593478721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1888741111.

The product of its digits is 10584000, while the sum is 59.

The spelling of 15115593478721 in words is "fifteen trillion, one hundred fifteen billion, five hundred ninety-three million, four hundred seventy-eight thousand, seven hundred twenty-one".