1289402400 has 648 divisors, whose sum is σ = 5266631664. Its totient is φ = 271564800.

The previous prime is 1289402393. The next prime is 1289402407. The reversal of 1289402400 is 42049821.

It is an interprime number because it is at equal distance from previous prime (1289402393) and next prime (1289402407).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1289402407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 75847192 + ... + 75847208.

It is an arithmetic number, because the mean of its divisors is an integer number (8127518).

Almost surely, 2^1289402400 is an apocalyptic number.

1289402400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1289402400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2633315832).

1289402400 is an abundant number, since it is smaller than the sum of its proper divisors (3977229264).

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

1289402400 is a wasteful number, since it uses less digits than its factorization.

1289402400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 1289402400 is about 35908.2497484909. The cubic root of 1289402400 is about 1088.4191093671.

The spelling of 1289402400 in words is "one billion, two hundred eighty-nine million, four hundred two thousand, four hundred".