684646402051 has 2 divisors, whose sum is σ = 684646402052. Its totient is φ = 684646402050.

The previous prime is 684646402043. The next prime is 684646402123. The reversal of 684646402051 is 150204646486.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 684646402051 - 2³ = 684646402043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 684646401992 and 684646402010.

It is not a weakly prime, because it can be changed into another prime (684646400051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342323201025 + 342323201026.

It is an arithmetic number, because the mean of its divisors is an integer number (342323201026).

Almost surely, 2^684646402051 is an apocalyptic number.

684646402051 is a deficient number, since it is larger than the sum of its proper divisors (1).

684646402051 is an equidigital number, since it uses as much as digits as its factorization.

684646402051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1105920, while the sum is 46.

The spelling of 684646402051 in words is "six hundred eighty-four billion, six hundred forty-six million, four hundred two thousand, fifty-one".