15503992875121 has 9 divisors (see below), whose sum is σ = 15574711346571. Its totient is φ = 15433594115952.

The previous prime is 15503992875103. The next prime is 15503992875149. The reversal of 15503992875121 is 12157829930551.

The square root of 15503992875121 is 3937511.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1853450802225 + 13650542072896 = 1361415^2 + 3694664^2 .

It is not a de Polignac number, because 15503992875121 - 2⁹ = 15503992874609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15503992873121) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 878056125 + ... + 878073781.

Almost surely, 2^{15503992875121} is an apocalyptic number.

15503992875121 is the 3937511-st square number.

15503992875121 is the 1968756-th centered octagonal number.

It is an amenable number.

15503992875121 is a deficient number, since it is larger than the sum of its proper divisors (70718471450).

15503992875121 is an frugal number, since it uses more digits than its factorization.

15503992875121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35760 (or 17880 counting only the distinct ones).

The product of its (nonzero) digits is 6804000, while the sum is 58.

The spelling of 15503992875121 in words is "fifteen trillion, five hundred three billion, nine hundred ninety-two million, eight hundred seventy-five thousand, one hundred twenty-one".