621217 has 2 divisors, whose sum is σ = 621218. Its totient is φ = 621216.

The previous prime is 621143. The next prime is 621223. The reversal of 621217 is 712126.

621217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 614656 + 6561 = 784^2 + 81^2 .

It is a cyclic number.

It is not a de Polignac number, because 621217 - 2¹¹ = 619169 is a prime.

It is a super-2 number, since 2×621217² = 771821122178, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 13 and base 14.

It is a junction number, because it is equal to n+sod(n) for n = 621194 and 621203.

It is not a weakly prime, because it can be changed into another prime (621227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310608 + 310609.

It is an arithmetic number, because the mean of its divisors is an integer number (310609).

2⁶²¹²¹⁷ is an apocalyptic number.

It is an amenable number.

621217 is a deficient number, since it is larger than the sum of its proper divisors (1).

621217 is an equidigital number, since it uses as much as digits as its factorization.

621217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 19.

The square root of 621217 is about 788.1732043149. The cubic root of 621217 is about 85.3259457445.

Subtracting 621217 from its reverse (712126), we obtain a palindrome (90909).

It can be divided in two parts, 62121 and 7, that added together give a triangular number (62128 = T₃₅₂).

The spelling of 621217 in words is "six hundred twenty-one thousand, two hundred seventeen".