7898778987 has 32 divisors (see below), whose sum is σ = 11641833216. Its totient is φ = 4723891200.

The previous prime is 7898778983. The next prime is 7898778991.

7898778987 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (7898778983) and next prime (7898778991).

It is not a de Polignac number, because 7898778987 - 2² = 7898778983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7898778983) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 864312 + ... + 873402.

It is an arithmetic number, because the mean of its divisors is an integer number (363807288).

Almost surely, 2^7898778987 is an apocalyptic number.

7898778987 is a deficient number, since it is larger than the sum of its proper divisors (3743054229).

7898778987 is a wasteful number, since it uses less digits than its factorization.

7898778987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9451.

The product of its digits is 796594176, while the sum is 78.

The square root of 7898778987 is about 88875.0751729640. The cubic root of 7898778987 is about 1991.5290880623.

It can be divided in two parts, 7898 and 778987, that added together give a triangular number (786885 = T₁₂₅₄).

The spelling of 7898778987 in words is "seven billion, eight hundred ninety-eight million, seven hundred seventy-eight thousand, nine hundred eighty-seven".