1361018557129 has 81 divisors (see below), whose sum is σ = 1769078287431. Its totient is φ = 1043244528480.

The previous prime is 1361018557123. The next prime is 1361018557133. The reversal of 1361018557129 is 9217558101631.

The square root of 1361018557129 is 1166627.

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., 948623404729 + 412395152400 = 973973^2 + 642180^2 .

It is not a de Polignac number, because 1361018557129 - 2³ = 1361018557121 is a prime.

It is a super-3 number, since 3×1361018557129³ (a number of 37 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (1361018557121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 9791500342 + ... + 9791500480.

Almost surely, 2^{1361018557129} is an apocalyptic number.

1361018557129 is the 1166627-th square number.

1361018557129 is the 583314-th centered octagonal number.

It is an amenable number.

1361018557129 is a deficient number, since it is larger than the sum of its proper divisors (408059730302).

1361018557129 is an equidigital number, since it uses as much as digits as its factorization.

1361018557129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532 (or 266 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 49.

Multiplying 1361018557129 by its sum of digits (49), we get a square (66689909299321 = 8166389²).

1361018557129 divided by its sum of digits (49) gives a square (27775888921 = 166661²).

The spelling of 1361018557129 in words is "one trillion, three hundred sixty-one billion, eighteen million, five hundred fifty-seven thousand, one hundred twenty-nine".