1684631645551 has 2 divisors, whose sum is σ = 1684631645552. Its totient is φ = 1684631645550.

The previous prime is 1684631645539. The next prime is 1684631645597. The reversal of 1684631645551 is 1555461364861.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1555461364861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1684631645551 - 2³⁵ = 1650271907183 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1684631645492 and 1684631645501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1684631645051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 842315822775 + 842315822776.

It is an arithmetic number, because the mean of its divisors is an integer number (842315822776).

Almost surely, 2^{1684631645551} is an apocalyptic number.

1684631645551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1684631645551 is an equidigital number, since it uses as much as digits as its factorization.

1684631645551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368000, while the sum is 55.

The spelling of 1684631645551 in words is "one trillion, six hundred eighty-four billion, six hundred thirty-one million, six hundred forty-five thousand, five hundred fifty-one".