1021209997 has 2 divisors, whose sum is σ = 1021209998. Its totient is φ = 1021209996.

The previous prime is 1021209983. The next prime is 1021210007. The reversal of 1021209997 is 7999021201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 527437156 + 493772841 = 22966^2 + 22221^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021209997 - 2¹⁵ = 1021177229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021201997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510604998 + 510604999.

It is an arithmetic number, because the mean of its divisors is an integer number (510604999).

Almost surely, 2^1021209997 is an apocalyptic number.

It is an amenable number.

1021209997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021209997 is an equidigital number, since it uses as much as digits as its factorization.

1021209997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 40.

The square root of 1021209997 is about 31956.3764685548. The cubic root of 1021209997 is about 1007.0205949018.

The spelling of 1021209997 in words is "one billion, twenty-one million, two hundred nine thousand, nine hundred ninety-seven".