684685081019 has 2 divisors, whose sum is σ = 684685081020. Its totient is φ = 684685081018.

The previous prime is 684685081009. The next prime is 684685081061. The reversal of 684685081019 is 910180586486.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 684685081019 - 2²⁰ = 684684032443 is a prime.

It is a super-2 number, since 2×684685081019² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (684685081009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342342540509 + 342342540510.

It is an arithmetic number, because the mean of its divisors is an integer number (342342540510).

Almost surely, 2^684685081019 is an apocalyptic number.

684685081019 is a deficient number, since it is larger than the sum of its proper divisors (1).

684685081019 is an equidigital number, since it uses as much as digits as its factorization.

684685081019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3317760, while the sum is 56.

The spelling of 684685081019 in words is "six hundred eighty-four billion, six hundred eighty-five million, eighty-one thousand, nineteen".