620209217 has 4 divisors (see below), whose sum is σ = 620472516. Its totient is φ = 619945920.

The previous prime is 620209193. The next prime is 620209223. The reversal of 620209217 is 712902026.

It is a Cunningham number, because it is equal to 24904²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 245360896 + 374848321 = 15664^2 + 19361^2 .

It is a cyclic number.

It is not a de Polignac number, because 620209217 - 2¹⁶ = 620143681 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 620209217.

It is not an unprimeable number, because it can be changed into a prime (620209277) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128084 + ... + 132837.

It is an arithmetic number, because the mean of its divisors is an integer number (155118129).

Almost surely, 2^620209217 is an apocalyptic number.

It is an amenable number.

620209217 is a deficient number, since it is larger than the sum of its proper divisors (263299).

620209217 is a wasteful number, since it uses less digits than its factorization.

620209217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263298.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 620209217 is about 24904.0000200771. Note that the first 4 decimals coincide. The cubic root of 620209217 is about 852.7978013766.

The spelling of 620209217 in words is "six hundred twenty million, two hundred nine thousand, two hundred seventeen".