6421656652241 has 4 divisors (see below), whose sum is σ = 6421676364852. Its totient is φ = 6421636939632.

The previous prime is 6421656652183. The next prime is 6421656652283. The reversal of 6421656652241 is 1422566561246.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2742468481600 + 3679188170641 = 1656040^2 + 1918121^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6421656652241 is a prime.

It is a super-2 number, since 2×6421656652241² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 6421656652241.

It is not an unprimeable number, because it can be changed into a prime (6421656652141) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 9359306 + ... + 10021971.

It is an arithmetic number, because the mean of its divisors is an integer number (1605419091213).

Almost surely, 2^{6421656652241} is an apocalyptic number.

It is an amenable number.

6421656652241 is a deficient number, since it is larger than the sum of its proper divisors (19712611).

6421656652241 is a wasteful number, since it uses less digits than its factorization.

6421656652241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19712610.

The product of its digits is 4147200, while the sum is 50.

The spelling of 6421656652241 in words is "six trillion, four hundred twenty-one billion, six hundred fifty-six million, six hundred fifty-two thousand, two hundred forty-one".