620879639 has 2 divisors, whose sum is σ = 620879640. Its totient is φ = 620879638.

The previous prime is 620879621. The next prime is 620879653. The reversal of 620879639 is 936978026.

620879639 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 is a cyclic number.

It is not a de Polignac number, because 620879639 - 2¹² = 620875543 is a prime.

It is a super-2 number, since 2×620879639² = 770983052249540642, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (620879659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310439819 + 310439820.

It is an arithmetic number, because the mean of its divisors is an integer number (310439820).

Almost surely, 2^620879639 is an apocalyptic number.

620879639 is a deficient number, since it is larger than the sum of its proper divisors (1).

620879639 is an equidigital number, since it uses as much as digits as its factorization.

620879639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 979776, while the sum is 50.

The square root of 620879639 is about 24917.4565114500. The cubic root of 620879639 is about 853.1049711229.

The spelling of 620879639 in words is "six hundred twenty million, eight hundred seventy-nine thousand, six hundred thirty-nine".