775220639 has 6 divisors (see below), whose sum is σ = 778896720. Its totient is φ = 771548400.

The previous prime is 775220629. The next prime is 775220659. The reversal of 775220639 is 936022577.

It is not a de Polignac number, because 775220639 - 2²⁸ = 506785183 is a prime.

It is a super-3 number, since 3×775220639³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 775220596 and 775220605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (775220629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 429539 + ... + 431339.

It is an arithmetic number, because the mean of its divisors is an integer number (129816120).

Almost surely, 2^775220639 is an apocalyptic number.

775220639 is a deficient number, since it is larger than the sum of its proper divisors (3676081).

775220639 is an frugal number, since it uses more digits than its factorization.

775220639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3841 (or 2040 counting only the distinct ones).

The product of its (nonzero) digits is 158760, while the sum is 41.

The square root of 775220639 is about 27842.7843255663. The cubic root of 775220639 is about 918.6324353001.

The spelling of 775220639 in words is "seven hundred seventy-five million, two hundred twenty thousand, six hundred thirty-nine".