1288921984249 has 9 divisors (see below), whose sum is σ = 1360353170703. Its totient is φ = 1221063549552.

The previous prime is 1288921984237. The next prime is 1288921984253. The reversal of 1288921984249 is 9424891298821.

The square root of 1288921984249 is 1135307.

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., 828109100025 + 460812884224 = 910005^2 + 678832^2 .

It is not a de Polignac number, because 1288921984249 - 2¹⁹ = 1288921459961 is a prime.

It is a super-2 number, since 2×1288921984249² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1288921985249) 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, 21540957 + ... + 21600709.

Almost surely, 2^{1288921984249} is an apocalyptic number.

1288921984249 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1288921984249 is the 1135307-th square number.

1288921984249 is the 567654-th centered octagonal number.

It is an amenable number.

1288921984249 is a deficient number, since it is larger than the sum of its proper divisors (71431186454).

1288921984249 is an frugal number, since it uses more digits than its factorization.

1288921984249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119544 (or 59772 counting only the distinct ones).

The product of its digits is 47775744, while the sum is 67.

The spelling of 1288921984249 in words is "one trillion, two hundred eighty-eight billion, nine hundred twenty-one million, nine hundred eighty-four thousand, two hundred forty-nine".