127121721 has 8 divisors (see below), whose sum is σ = 171538080. Its totient is φ = 83726592.

The previous prime is 127121707. The next prime is 127121741.

127121721 is nontrivially palindromic in base 10.

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

It is not a de Polignac number, because 127121721 - 2¹⁹ = 126597433 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 127121691 and 127121700.

It is not an unprimeable number, because it can be changed into a prime (127121741) 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, 255016 + ... + 255513.

It is an arithmetic number, because the mean of its divisors is an integer number (21442260).

Almost surely, 2^127121721 is an apocalyptic number.

It is an amenable number.

127121721 is a deficient number, since it is larger than the sum of its proper divisors (44416359).

127121721 is an equidigital number, since it uses as much as digits as its factorization.

127121721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510615.

The product of its digits is 392, while the sum is 24.

The square root of 127121721 is about 11274.8268722850. The cubic root of 127121721 is about 502.8131045368.

The spelling of 127121721 in words is "one hundred twenty-seven million, one hundred twenty-one thousand, seven hundred twenty-one".