7978544038 has 4 divisors (see below), whose sum is σ = 11967816060. Its totient is φ = 3989272018.

The previous prime is 7978543967. The next prime is 7978544047. The reversal of 7978544038 is 8304458797.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8304458797 = 7127 ⋅1165211.

It is a self number, because there is not a number n which added to its sum of digits gives 7978544038.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1994636008 + ... + 1994636011.

It is an arithmetic number, because the mean of its divisors is an integer number (2991954015).

Almost surely, 2^7978544038 is an apocalyptic number.

7978544038 is a deficient number, since it is larger than the sum of its proper divisors (3989272022).

7978544038 is a wasteful number, since it uses less digits than its factorization.

7978544038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3989272021.

The product of its (nonzero) digits is 6773760, while the sum is 55.

The square root of 7978544038 is about 89322.6960967928. The cubic root of 7978544038 is about 1998.2104023144.

The spelling of 7978544038 in words is "seven billion, nine hundred seventy-eight million, five hundred forty-four thousand, thirty-eight".