2155385143129 has 9 divisors (see below), whose sum is σ = 2215269048447. Its totient is φ = 2097078638184.

The previous prime is 2155385143123. The next prime is 2155385143147. The reversal of 2155385143129 is 9213415835512.

The square root of 2155385143129 is 1468123.

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., 1928668225225 + 226716917904 = 1388765^2 + 476148^2 .

It is not a de Polignac number, because 2155385143129 - 2⁵ = 2155385143097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2155385143123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 54300712 + ... + 54340390.

It is an arithmetic number, because the mean of its divisors is an integer number (246141005383).

Almost surely, 2^{2155385143129} is an apocalyptic number.

2155385143129 is the 1468123-rd square number.

2155385143129 is the 734062-nd centered octagonal number.

It is an amenable number.

2155385143129 is a deficient number, since it is larger than the sum of its proper divisors (59883905318).

2155385143129 is an frugal number, since it uses more digits than its factorization.

2155385143129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79432 (or 39716 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 49.

Multiplying 2155385143129 by its sum of digits (49), we get a square (105613872013321 = 10276861²).

The spelling of 2155385143129 in words is "two trillion, one hundred fifty-five billion, three hundred eighty-five million, one hundred forty-three thousand, one hundred twenty-nine".