61636446643 has 2 divisors, whose sum is σ = 61636446644. Its totient is φ = 61636446642.

The previous prime is 61636446631. The next prime is 61636446659. The reversal of 61636446643 is 34664463616.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61636446643 is a prime.

It is not a weakly prime, because it can be changed into another prime (61636446343) 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 as a sum of consecutive naturals, namely, 30818223321 + 30818223322.

It is an arithmetic number, because the mean of its divisors is an integer number (30818223322).

Almost surely, 2^61636446643 is an apocalyptic number.

61636446643 is a deficient number, since it is larger than the sum of its proper divisors (1).

61636446643 is an equidigital number, since it uses as much as digits as its factorization.

61636446643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4478976, while the sum is 49.

The spelling of 61636446643 in words is "sixty-one billion, six hundred thirty-six million, four hundred forty-six thousand, six hundred forty-three".