1278662398 has 16 divisors (see below), whose sum is σ = 2074640400. Its totient is φ = 587549376.

The previous prime is 1278662383. The next prime is 1278662417. The reversal of 1278662398 is 8932668721.

It is a super-2 number, since 2×1278662398² = 3269955056118220808, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 102423 + ... + 114226.

It is an arithmetic number, because the mean of its divisors is an integer number (129665025).

Almost surely, 2^1278662398 is an apocalyptic number.

1278662398 is a deficient number, since it is larger than the sum of its proper divisors (795978002).

1278662398 is a wasteful number, since it uses less digits than its factorization.

1278662398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216891.

The product of its digits is 1741824, while the sum is 52.

The square root of 1278662398 is about 35758.3891975016. The cubic root of 1278662398 is about 1085.3887053982.

The spelling of 1278662398 in words is "one billion, two hundred seventy-eight million, six hundred sixty-two thousand, three hundred ninety-eight".