721210 has 16 divisors (see below), whose sum is σ = 1483776. Its totient is φ = 247248.

The previous prime is 721207. The next prime is 721213. The reversal of 721210 is 12127.

It is an interprime number because it is at equal distance from previous prime (721207) and next prime (721213).

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (721213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5082 + ... + 5221.

It is an arithmetic number, because the mean of its divisors is an integer number (92736).

2⁷²¹²¹⁰ is an apocalyptic number.

721210 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

721210 is an abundant number, since it is smaller than the sum of its proper divisors (762566).

It is a weird number, because it is abundant, but not a pseudoperfect number.

721210 is a wasteful number, since it uses less digits than its factorization.

721210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10317.

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 721210 is about 849.2408374543. The cubic root of 721210 is about 89.6782751624.

Adding to 721210 its reverse (12127), we get a palindrome (733337).

The spelling of 721210 in words is "seven hundred twenty-one thousand, two hundred ten", and thus it is an iban number.