21235001 has 2 divisors, whose sum is σ = 21235002. Its totient is φ = 21235000.

The previous prime is 21234973. The next prime is 21235009. The reversal of 21235001 is 10053212.

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., 18835600 + 2399401 = 4340^2 + 1549^2 .

It is a cyclic number.

It is not a de Polignac number, because 21235001 - 2⁶ = 21234937 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21235009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617500 + 10617501.

It is an arithmetic number, because the mean of its divisors is an integer number (10617501).

Almost surely, 2^21235001 is an apocalyptic number.

It is an amenable number.

21235001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21235001 is an equidigital number, since it uses as much as digits as its factorization.

21235001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 21235001 is about 4608.1450715011. The cubic root of 21235001 is about 276.9177293938.

Adding to 21235001 its reverse (10053212), we get a palindrome (31288213).

The spelling of 21235001 in words is "twenty-one million, two hundred thirty-five thousand, one".