7978152991 has 16 divisors (see below), whose sum is σ = 8883267840. Its totient is φ = 7130566080.

The previous prime is 7978152971. The next prime is 7978153013. The reversal of 7978152991 is 1992518797.

7978152991 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 7978152991 - 2¹⁵ = 7978120223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7978152971) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 93145 + ... + 156946.

It is an arithmetic number, because the mean of its divisors is an integer number (555204240).

Almost surely, 2^7978152991 is an apocalyptic number.

7978152991 is a deficient number, since it is larger than the sum of its proper divisors (905114849).

7978152991 is a wasteful number, since it uses less digits than its factorization.

7978152991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250206.

The product of its digits is 2857680, while the sum is 58.

The square root of 7978152991 is about 89320.5071134283. The cubic root of 7978152991 is about 1998.1777561346.

The spelling of 7978152991 in words is "seven billion, nine hundred seventy-eight million, one hundred fifty-two thousand, nine hundred ninety-one".