102210721 has 4 divisors (see below), whose sum is σ = 102695344. Its totient is φ = 101726100.

The previous prime is 102210697. The next prime is 102210733. The reversal of 102210721 is 127012201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 102210721 - 2⁷ = 102210593 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102210695 and 102210704.

It is not an unprimeable number, because it can be changed into a prime (102210791) 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 in 3 ways as a sum of consecutive naturals, for example, 241995 + ... + 242416.

It is an arithmetic number, because the mean of its divisors is an integer number (25673836).

Almost surely, 2^102210721 is an apocalyptic number.

It is an amenable number.

102210721 is a deficient number, since it is larger than the sum of its proper divisors (484623).

102210721 is an equidigital number, since it uses as much as digits as its factorization.

102210721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484622.

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

The square root of 102210721 is about 10109.9317999678. The cubic root of 102210721 is about 467.5544024311.

Adding to 102210721 its reverse (127012201), we get a palindrome (229222922).

The spelling of 102210721 in words is "one hundred two million, two hundred ten thousand, seven hundred twenty-one".