1655055121 has 2 divisors, whose sum is σ = 1655055122. Its totient is φ = 1655055120.

The previous prime is 1655055119. The next prime is 1655055139. The reversal of 1655055121 is 1215505561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1654862400 + 192721 = 40680^2 + 439^2 .

It is an emirp because it is prime and its reverse (1215505561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1655055121 - 2¹ = 1655055119 is a prime.

Together with 1655055119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1655055821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827527560 + 827527561.

It is an arithmetic number, because the mean of its divisors is an integer number (827527561).

Almost surely, 2^1655055121 is an apocalyptic number.

It is an amenable number.

1655055121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1655055121 is an equidigital number, since it uses as much as digits as its factorization.

1655055121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7500, while the sum is 31.

The square root of 1655055121 is about 40682.3686748940. The cubic root of 1655055121 is about 1182.8712804459.

The spelling of 1655055121 in words is "one billion, six hundred fifty-five million, fifty-five thousand, one hundred twenty-one".