2817989021 has 2 divisors, whose sum is σ = 2817989022. Its totient is φ = 2817989020.

The previous prime is 2817988993. The next prime is 2817989087. The reversal of 2817989021 is 1209897182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2702856121 + 115132900 = 51989^2 + 10730^2 .

It is a cyclic number.

It is not a de Polignac number, because 2817989021 - 2¹⁴ = 2817972637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2817989221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1408994510 + 1408994511.

It is an arithmetic number, because the mean of its divisors is an integer number (1408994511).

Almost surely, 2^2817989021 is an apocalyptic number.

It is an amenable number.

2817989021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2817989021 is an equidigital number, since it uses as much as digits as its factorization.

2817989021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 47.

The square root of 2817989021 is about 53084.7343499052. The cubic root of 2817989021 is about 1412.4717339581.

The spelling of 2817989021 in words is "two billion, eight hundred seventeen million, nine hundred eighty-nine thousand, twenty-one".