643709444907346 has 16 divisors (see below), whose sum is σ = 1031409511419384. Its totient is φ = 300241365243904.

The previous prime is 643709444907293. The next prime is 643709444907377.

643709444907346 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 266474967531721 + 377234477375625 = 16324061^2 + 19422525^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83772698515 + ... + 83772706198.

Almost surely, 2^{643709444907346} is an apocalyptic number.

643709444907346 is a deficient number, since it is larger than the sum of its proper divisors (387700066512038).

643709444907346 is a wasteful number, since it uses less digits than its factorization.

643709444907346 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167545404845.

The product of its (nonzero) digits is 1316818944, while the sum is 70.

The spelling of 643709444907346 in words is "six hundred forty-three trillion, seven hundred nine billion, four hundred forty-four million, nine hundred seven thousand, three hundred forty-six".