127724561 has 2 divisors, whose sum is σ = 127724562. Its totient is φ = 127724560.

The previous prime is 127724537. The next prime is 127724563. The reversal of 127724561 is 165427721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120670225 + 7054336 = 10985^2 + 2656^2 .

It is a cyclic number.

It is not a de Polignac number, because 127724561 - 2¹⁰ = 127723537 is a prime.

Together with 127724563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (127724563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63862280 + 63862281.

It is an arithmetic number, because the mean of its divisors is an integer number (63862281).

Almost surely, 2^127724561 is an apocalyptic number.

It is an amenable number.

127724561 is a deficient number, since it is larger than the sum of its proper divisors (1).

127724561 is an equidigital number, since it uses as much as digits as its factorization.

127724561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23520, while the sum is 35.

The square root of 127724561 is about 11301.5291443238. The cubic root of 127724561 is about 503.6066693185.

The spelling of 127724561 in words is "one hundred twenty-seven million, seven hundred twenty-four thousand, five hundred sixty-one".