42911536721 has 2 divisors, whose sum is σ = 42911536722. Its totient is φ = 42911536720.

The previous prime is 42911536709. The next prime is 42911536897. The reversal of 42911536721 is 12763511924.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42826233025 + 85303696 = 206945^2 + 9236^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42911536721 is a prime.

It is not a weakly prime, because it can be changed into another prime (42911535721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21455768360 + 21455768361.

It is an arithmetic number, because the mean of its divisors is an integer number (21455768361).

Almost surely, 2^42911536721 is an apocalyptic number.

It is an amenable number.

42911536721 is a deficient number, since it is larger than the sum of its proper divisors (1).

42911536721 is an equidigital number, since it uses as much as digits as its factorization.

42911536721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The spelling of 42911536721 in words is "forty-two billion, nine hundred eleven million, five hundred thirty-six thousand, seven hundred twenty-one".