641436870172816 has 45 divisors (see below), whose sum is σ = 1244090774023129. Its totient is φ = 320381540600000.

The previous prime is 641436870172793. The next prime is 641436870172937. The reversal of 641436870172816 is 618271078634146.

The square root of 641436870172816 is 25326604.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 629829493731216 + 11607376441600 = 25096404^2 + 3406960^2 .

It is a super-2 number, since 2×641436870172816² (a number of 30 digits) contains 22 as substring.

It is a Duffinian 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 in 8 ways as a sum of consecutive naturals, for example, 116603682066 + ... + 116603687566.

Almost surely, 2^{641436870172816} is an apocalyptic number.

641436870172816 is the 25326604-th square number.

It is an amenable number.

641436870172816 is a deficient number, since it is larger than the sum of its proper divisors (602653903850313).

641436870172816 is an frugal number, since it uses more digits than its factorization.

641436870172816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13312 (or 6654 counting only the distinct ones).

The product of its (nonzero) digits is 65028096, while the sum is 64.

The spelling of 641436870172816 in words is "six hundred forty-one trillion, four hundred thirty-six billion, eight hundred seventy million, one hundred seventy-two thousand, eight hundred sixteen".