2055665021 has 2 divisors, whose sum is σ = 2055665022. Its totient is φ = 2055665020.

The previous prime is 2055664993. The next prime is 2055665063. The reversal of 2055665021 is 1205665502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1959036121 + 96628900 = 44261^2 + 9830^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2055665021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2055665921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1027832510 + 1027832511.

It is an arithmetic number, because the mean of its divisors is an integer number (1027832511).

Almost surely, 2^2055665021 is an apocalyptic number.

It is an amenable number.

2055665021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2055665021 is an equidigital number, since it uses as much as digits as its factorization.

2055665021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18000, while the sum is 32.

The square root of 2055665021 is about 45339.4422219771. The cubic root of 2055665021 is about 1271.5031741552.

The spelling of 2055665021 in words is "two billion, fifty-five million, six hundred sixty-five thousand, twenty-one".