1299529320961 has 9 divisors (see below), whose sum is σ = 1380489450249. Its totient is φ = 1223068180224.

The previous prime is 1299529320959. The next prime is 1299529321091. The reversal of 1299529320961 is 1690239259921.

The square root of 1299529320961 is 1139969.

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

It can be written as a sum of positive squares in 4 ways, for example, as 640769831361 + 658759489600 = 800481^2 + 811640^2 .

It is not a de Polignac number, because 1299529320961 - 2¹ = 1299529320959 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1299529320896 and 1299529320905.

It is not an unprimeable number, because it can be changed into a prime (1299529020961) 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, 19345945 + ... + 19413001.

Almost surely, 2^{1299529320961} is an apocalyptic number.

1299529320961 is the 1139969-th square number.

1299529320961 is the 569985-th centered octagonal number.

It is an amenable number.

1299529320961 is a deficient number, since it is larger than the sum of its proper divisors (80960129288).

1299529320961 is an frugal number, since it uses more digits than its factorization.

1299529320961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134148 (or 67074 counting only the distinct ones).

The product of its (nonzero) digits is 4723920, while the sum is 58.

The spelling of 1299529320961 in words is "one trillion, two hundred ninety-nine billion, five hundred twenty-nine million, three hundred twenty thousand, nine hundred sixty-one".