2178648971 has 2 divisors, whose sum is σ = 2178648972. Its totient is φ = 2178648970.

The previous prime is 2178648959. The next prime is 2178649001. The reversal of 2178648971 is 1798468712.

It is a happy number.

2178648971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2178648971 - 2¹⁸ = 2178386827 is a prime.

It is a super-2 number, since 2×2178648971² = 9493022677678717682, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (2178648071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1089324485 + 1089324486.

It is an arithmetic number, because the mean of its divisors is an integer number (1089324486).

Almost surely, 2^2178648971 is an apocalyptic number.

2178648971 is a deficient number, since it is larger than the sum of its proper divisors (1).

2178648971 is an equidigital number, since it uses as much as digits as its factorization.

2178648971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1354752, while the sum is 53.

The square root of 2178648971 is about 46675.9999464393. Note that the first 4 decimals coincide. The cubic root of 2178648971 is about 1296.3703429226.

The spelling of 2178648971 in words is "two billion, one hundred seventy-eight million, six hundred forty-eight thousand, nine hundred seventy-one".