1288634398 has 8 divisors (see below), whose sum is σ = 1959430608. Its totient is φ = 635490864.

The previous prime is 1288634393. The next prime is 1288634441. The reversal of 1288634398 is 8934368821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1288634398² = 3321157223417644808, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1288634393) 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 3 ways as a sum of consecutive naturals, for example, 4412986 + ... + 4413277.

It is an arithmetic number, because the mean of its divisors is an integer number (244928826).

Almost surely, 2^1288634398 is an apocalyptic number.

1288634398 is a deficient number, since it is larger than the sum of its proper divisors (670796210).

1288634398 is an equidigital number, since it uses as much as digits as its factorization.

1288634398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8826338.

The product of its digits is 1990656, while the sum is 52.

The square root of 1288634398 is about 35897.5542063801. The cubic root of 1288634398 is about 1088.2029694275.

The spelling of 1288634398 in words is "one billion, two hundred eighty-eight million, six hundred thirty-four thousand, three hundred ninety-eight".