127797721 has 8 divisors (see below), whose sum is σ = 135881064. Its totient is φ = 119777280.

The previous prime is 127797707. The next prime is 127797731.

127797721 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 49280400 + 78517321 = 7020^2 + 8861^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 127797721 - 2²³ = 119409113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (127797701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11500 + ... + 19693.

It is an arithmetic number, because the mean of its divisors is an integer number (16985133).

Almost surely, 2^127797721 is an apocalyptic number.

It is an amenable number.

127797721 is a deficient number, since it is larger than the sum of its proper divisors (8083343).

127797721 is a wasteful number, since it uses less digits than its factorization.

127797721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31451.

The product of its digits is 86436, while the sum is 43.

The square root of 127797721 is about 11304.7654110999. The cubic root of 127797721 is about 503.7028054393.

The spelling of 127797721 in words is "one hundred twenty-seven million, seven hundred ninety-seven thousand, seven hundred twenty-one".