7898478638 has 16 divisors (see below), whose sum is σ = 12646938240. Its totient is φ = 3688687800.

The previous prime is 7898478571. The next prime is 7898478667. The reversal of 7898478638 is 8368748987.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1461068 + ... + 1466463.

It is an arithmetic number, because the mean of its divisors is an integer number (790433640).

Almost surely, 2^7898478638 is an apocalyptic number.

7898478638 is a deficient number, since it is larger than the sum of its proper divisors (4748459602).

7898478638 is a wasteful number, since it uses less digits than its factorization.

7898478638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2927623.

The product of its digits is 130056192, while the sum is 68.

The square root of 7898478638 is about 88873.3854311852. The cubic root of 7898478638 is about 1991.5038452852.

The spelling of 7898478638 in words is "seven billion, eight hundred ninety-eight million, four hundred seventy-eight thousand, six hundred thirty-eight".