1127421728921 has 2 divisors, whose sum is σ = 1127421728922. Its totient is φ = 1127421728920.

The previous prime is 1127421728903. The next prime is 1127421728957. The reversal of 1127421728921 is 1298271247211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 966753031696 + 160668697225 = 983236^2 + 400835^2 .

It is a cyclic number.

It is not a de Polignac number, because 1127421728921 - 2¹⁴ = 1127421712537 is a prime.

It is not a weakly prime, because it can be changed into another prime (1127421728971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 563710864460 + 563710864461.

It is an arithmetic number, because the mean of its divisors is an integer number (563710864461).

Almost surely, 2^{1127421728921} is an apocalyptic number.

It is an amenable number.

1127421728921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1127421728921 is an equidigital number, since it uses as much as digits as its factorization.

1127421728921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 47.

The spelling of 1127421728921 in words is "one trillion, one hundred twenty-seven billion, four hundred twenty-one million, seven hundred twenty-eight thousand, nine hundred twenty-one".