6240643561 has 2 divisors, whose sum is σ = 6240643562. Its totient is φ = 6240643560.

The previous prime is 6240643553. The next prime is 6240643583. The reversal of 6240643561 is 1653460426.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4921864336 + 1318779225 = 70156^2 + 36315^2 .

It is a cyclic number.

It is not a de Polignac number, because 6240643561 - 2³ = 6240643553 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6240643561.

It is not a weakly prime, because it can be changed into another prime (6240643501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3120321780 + 3120321781.

It is an arithmetic number, because the mean of its divisors is an integer number (3120321781).

Almost surely, 2^6240643561 is an apocalyptic number.

It is an amenable number.

6240643561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6240643561 is an equidigital number, since it uses as much as digits as its factorization.

6240643561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 37.

The square root of 6240643561 is about 78997.7440247505. The cubic root of 6240643561 is about 1841.0961058296.

The spelling of 6240643561 in words is "six billion, two hundred forty million, six hundred forty-three thousand, five hundred sixty-one".