1021099997 has 2 divisors, whose sum is σ = 1021099998. Its totient is φ = 1021099996.

The previous prime is 1021099991. The next prime is 1021099999. The reversal of 1021099997 is 7999901201.

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., 587044441 + 434055556 = 24229^2 + 20834^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021099997 - 2⁸ = 1021099741 is a prime.

Together with 1021099999, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021099991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510549998 + 510549999.

It is an arithmetic number, because the mean of its divisors is an integer number (510549999).

Almost surely, 2^1021099997 is an apocalyptic number.

It is an amenable number.

1021099997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021099997 is an equidigital number, since it uses as much as digits as its factorization.

1021099997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 91854, while the sum is 47.

The square root of 1021099997 is about 31954.6553259459. The cubic root of 1021099997 is about 1006.9844364090.

The spelling of 1021099997 in words is "one billion, twenty-one million, ninety-nine thousand, nine hundred ninety-seven".