21517225001 has 2 divisors, whose sum is σ = 21517225002. Its totient is φ = 21517225000.

The previous prime is 21517224943. The next prime is 21517225043. The reversal of 21517225001 is 10052271512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13064261401 + 8452963600 = 114299^2 + 91940^2 .

It is a cyclic number.

It is not a de Polignac number, because 21517225001 - 2²² = 21513030697 is a prime.

It is not a weakly prime, because it can be changed into another prime (21517225801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10758612500 + 10758612501.

It is an arithmetic number, because the mean of its divisors is an integer number (10758612501).

Almost surely, 2^21517225001 is an apocalyptic number.

It is an amenable number.

21517225001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21517225001 is an equidigital number, since it uses as much as digits as its factorization.

21517225001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1400, while the sum is 26.

Adding to 21517225001 its reverse (10052271512), we get a palindrome (31569496513).

The spelling of 21517225001 in words is "twenty-one billion, five hundred seventeen million, two hundred twenty-five thousand, one".