102201721 has 2 divisors, whose sum is σ = 102201722. Its totient is φ = 102201720.

The previous prime is 102201709. The next prime is 102201727. The reversal of 102201721 is 127102201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67815225 + 34386496 = 8235^2 + 5864^2 .

It is a cyclic number.

It is not a de Polignac number, because 102201721 - 2¹¹ = 102199673 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 102201695 and 102201704.

It is not a weakly prime, because it can be changed into another prime (102201727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51100860 + 51100861.

It is an arithmetic number, because the mean of its divisors is an integer number (51100861).

Almost surely, 2^102201721 is an apocalyptic number.

It is an amenable number.

102201721 is a deficient number, since it is larger than the sum of its proper divisors (1).

102201721 is an equidigital number, since it uses as much as digits as its factorization.

102201721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 102201721 is about 10109.4866833089. The cubic root of 102201721 is about 467.5406787789.

Adding to 102201721 its reverse (127102201), we get a palindrome (229303922).

The spelling of 102201721 in words is "one hundred two million, two hundred one thousand, seven hundred twenty-one".