1289997198864 has 480 divisors, whose sum is σ = 4183652229120. Its totient is φ = 381447014400.

The previous prime is 1289997198863. The next prime is 1289997198869. The reversal of 1289997198864 is 4688917999821.

It is a happy number.

1289997198864 is a `hidden beast` number, since 1 + 289 + 9 + 97 + 198 + 8 + 64 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (1289997198863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 866350632 + ... + 866352120.

It is an arithmetic number, because the mean of its divisors is an integer number (8715942144).

Almost surely, 2^{1289997198864} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1289997198864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2091826114560).

1289997198864 is an abundant number, since it is smaller than the sum of its proper divisors (2893655030256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1289997198864 is a wasteful number, since it uses less digits than its factorization.

1289997198864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001 (or 1983 counting only the distinct ones).

The product of its digits is 1128701952, while the sum is 81.

The spelling of 1289997198864 in words is "one trillion, two hundred eighty-nine billion, nine hundred ninety-seven million, one hundred ninety-eight thousand, eight hundred sixty-four".