21030797 has 2 divisors, whose sum is σ = 21030798. Its totient is φ = 21030796.

The previous prime is 21030791. The next prime is 21030857. The reversal of 21030797 is 79703012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20484676 + 546121 = 4526^2 + 739^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030797 - 2⁴ = 21030781 is a prime.

It is a Chen prime.

It is equal to p_1331795 and since 21030797 and 1331795 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21030791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515398 + 10515399.

It is an arithmetic number, because the mean of its divisors is an integer number (10515399).

Almost surely, 2^21030797 is an apocalyptic number.

It is an amenable number.

21030797 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030797 is an equidigital number, since it uses as much as digits as its factorization.

21030797 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2646, while the sum is 29.

The square root of 21030797 is about 4585.9346920775. The cubic root of 21030797 is about 276.0272193627.

The spelling of 21030797 in words is "twenty-one million, thirty thousand, seven hundred ninety-seven".