16434221261 has 2 divisors, whose sum is σ = 16434221262. Its totient is φ = 16434221260.

The previous prime is 16434221231. The next prime is 16434221311. The reversal of 16434221261 is 16212243461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13297549225 + 3136672036 = 115315^2 + 56006^2 .

It is a cyclic number.

It is not a de Polignac number, because 16434221261 - 2¹⁰ = 16434220237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16434221231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8217110630 + 8217110631.

It is an arithmetic number, because the mean of its divisors is an integer number (8217110631).

Almost surely, 2^16434221261 is an apocalyptic number.

It is an amenable number.

16434221261 is a deficient number, since it is larger than the sum of its proper divisors (1).

16434221261 is an equidigital number, since it uses as much as digits as its factorization.

16434221261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 32.

The spelling of 16434221261 in words is "sixteen billion, four hundred thirty-four million, two hundred twenty-one thousand, two hundred sixty-one".