7978642442 has 16 divisors (see below), whose sum is σ = 12059864712. Its totient is φ = 3958709760.

The previous prime is 7978642421. The next prime is 7978642447. The reversal of 7978642442 is 2442468797.

It can be written as a sum of positive squares in 4 ways, for example, as 7305291841 + 673350601 = 85471^2 + 25949^2 .

It is not an unprimeable number, because it can be changed into a prime (7978642447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1227842 + ... + 1234322.

Almost surely, 2^7978642442 is an apocalyptic number.

7978642442 is a deficient number, since it is larger than the sum of its proper divisors (4081222270).

7978642442 is a wasteful number, since it uses less digits than its factorization.

7978642442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11113.

The product of its digits is 5419008, while the sum is 53.

The square root of 7978642442 is about 89323.2469293409. The cubic root of 7978642442 is about 1998.2186173089.

The spelling of 7978642442 in words is "seven billion, nine hundred seventy-eight million, six hundred forty-two thousand, four hundred forty-two".