646259498078 has 4 divisors (see below), whose sum is σ = 969389247120. Its totient is φ = 323129749038.

The previous prime is 646259498057. The next prime is 646259498083. The reversal of 646259498078 is 870894952646.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 646259497999 and 646259498017.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161564874518 + ... + 161564874521.

It is an arithmetic number, because the mean of its divisors is an integer number (242347311780).

Almost surely, 2^646259498078 is an apocalyptic number.

646259498078 is a deficient number, since it is larger than the sum of its proper divisors (323129749042).

646259498078 is a wasteful number, since it uses less digits than its factorization.

646259498078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323129749041.

The product of its (nonzero) digits is 209018880, while the sum is 68.

The spelling of 646259498078 in words is "six hundred forty-six billion, two hundred fifty-nine million, four hundred ninety-eight thousand, seventy-eight".