620428990970809 has 2 divisors, whose sum is σ = 620428990970810. Its totient is φ = 620428990970808.

The previous prime is 620428990970801. The next prime is 620428990970903. The reversal of 620428990970809 is 908079099824026.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 333641641539600 + 286787349431209 = 18265860^2 + 16934797^2 .

It is a cyclic number.

It is not a de Polignac number, because 620428990970809 - 2³ = 620428990970801 is a prime.

It is a super-2 number, since 2×620428990970809² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (620428990970801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310214495485404 + 310214495485405.

It is an arithmetic number, because the mean of its divisors is an integer number (310214495485405).

Almost surely, 2^{620428990970809} is an apocalyptic number.

It is an amenable number.

620428990970809 is a deficient number, since it is larger than the sum of its proper divisors (1).

620428990970809 is an equidigital number, since it uses as much as digits as its factorization.

620428990970809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282175488, while the sum is 73.

The spelling of 620428990970809 in words is "six hundred twenty trillion, four hundred twenty-eight billion, nine hundred ninety million, nine hundred seventy thousand, eight hundred nine".