162721729 has 2 divisors, whose sum is σ = 162721730. Its totient is φ = 162721728.

The previous prime is 162721721. The next prime is 162721747. The reversal of 162721729 is 927127261.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 119793025 + 42928704 = 10945^2 + 6552^2 .

It is a cyclic number.

It is not a de Polignac number, because 162721729 - 2³ = 162721721 is a prime.

It is a super-2 number, since 2×162721729² = 52956722177498882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (162721721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81360864 + 81360865.

It is an arithmetic number, because the mean of its divisors is an integer number (81360865).

Almost surely, 2^162721729 is an apocalyptic number.

It is an amenable number.

162721729 is a deficient number, since it is larger than the sum of its proper divisors (1).

162721729 is an equidigital number, since it uses as much as digits as its factorization.

162721729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 37.

The square root of 162721729 is about 12756.2427462008. The cubic root of 162721729 is about 545.9445271412.

The spelling of 162721729 in words is "one hundred sixty-two million, seven hundred twenty-one thousand, seven hundred twenty-nine".