5671161721 has 2 divisors, whose sum is σ = 5671161722. Its totient is φ = 5671161720.

The previous prime is 5671161709. The next prime is 5671161823. The reversal of 5671161721 is 1271611765.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5060330496 + 610831225 = 71136^2 + 24715^2 .

It is a cyclic number.

It is not a de Polignac number, because 5671161721 - 2¹⁹ = 5670637433 is a prime.

It is not a weakly prime, because it can be changed into another prime (5671168721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2835580860 + 2835580861.

It is an arithmetic number, because the mean of its divisors is an integer number (2835580861).

Almost surely, 2^5671161721 is an apocalyptic number.

It is an amenable number.

5671161721 is a deficient number, since it is larger than the sum of its proper divisors (1).

5671161721 is an equidigital number, since it uses as much as digits as its factorization.

5671161721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17640, while the sum is 37.

The square root of 5671161721 is about 75307.1160050629. The cubic root of 5671161721 is about 1783.2983619737.

The spelling of 5671161721 in words is "five billion, six hundred seventy-one million, one hundred sixty-one thousand, seven hundred twenty-one".