2178435638651 has 2 divisors, whose sum is σ = 2178435638652. Its totient is φ = 2178435638650.

The previous prime is 2178435638623. The next prime is 2178435638653. The reversal of 2178435638651 is 1568365348712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2178435638651 - 2¹⁴ = 2178435622267 is a prime.

Together with 2178435638653, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2178435638653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1089217819325 + 1089217819326.

It is an arithmetic number, because the mean of its divisors is an integer number (1089217819326).

Almost surely, 2^{2178435638651} is an apocalyptic number.

2178435638651 is a deficient number, since it is larger than the sum of its proper divisors (1).

2178435638651 is an equidigital number, since it uses as much as digits as its factorization.

2178435638651 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29030400, while the sum is 59.

The spelling of 2178435638651 in words is "two trillion, one hundred seventy-eight billion, four hundred thirty-five million, six hundred thirty-eight thousand, six hundred fifty-one".