2197939021 has 2 divisors, whose sum is σ = 2197939022. Its totient is φ = 2197939020.

The previous prime is 2197938983. The next prime is 2197939123. The reversal of 2197939021 is 1209397912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1830641796 + 367297225 = 42786^2 + 19165^2 .

It is a cyclic number.

It is not a de Polignac number, because 2197939021 - 2³¹ = 50455373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2197939721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1098969510 + 1098969511.

It is an arithmetic number, because the mean of its divisors is an integer number (1098969511).

Almost surely, 2^2197939021 is an apocalyptic number.

It is an amenable number.

2197939021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2197939021 is an equidigital number, since it uses as much as digits as its factorization.

2197939021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 2197939021 is about 46882.1823404159. The cubic root of 2197939021 is about 1300.1851848618.

The spelling of 2197939021 in words is "two billion, one hundred ninety-seven million, nine hundred thirty-nine thousand, twenty-one".