21010097 has 2 divisors, whose sum is σ = 21010098. Its totient is φ = 21010096.

The previous prime is 21010069. The next prime is 21010111. The reversal of 21010097 is 79001012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12967201 + 8042896 = 3601^2 + 2836^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21010097 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21010037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505048 + 10505049.

It is an arithmetic number, because the mean of its divisors is an integer number (10505049).

Almost surely, 2^21010097 is an apocalyptic number.

It is an amenable number.

21010097 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010097 is an equidigital number, since it uses as much as digits as its factorization.

21010097 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 126, while the sum is 20.

The square root of 21010097 is about 4583.6772355828. The cubic root of 21010097 is about 275.9366277873.

The spelling of 21010097 in words is "twenty-one million, ten thousand, ninety-seven".