778272769 has 8 divisors (see below), whose sum is σ = 781221672. Its totient is φ = 775330560.

The previous prime is 778272749. The next prime is 778272787. The reversal of 778272769 is 967272877.

It can be written as a sum of positive squares in 4 ways, for example, as 102272769 + 676000000 = 10113^2 + 26000^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 778272769 - 2¹⁹ = 777748481 is a prime.

It is a super-2 number, since 2×778272769² = 1211417005933854722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (778272749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 362439 + ... + 364579.

It is an arithmetic number, because the mean of its divisors is an integer number (97652709).

It is a Proth number, since it is equal to 23751 ⋅ 2¹⁵ + 1 and 23751 < 2¹⁵.

Almost surely, 2^778272769 is an apocalyptic number.

It is an amenable number.

778272769 is a deficient number, since it is larger than the sum of its proper divisors (2948903).

778272769 is a wasteful number, since it uses less digits than its factorization.

778272769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3347.

The product of its digits is 4148928, while the sum is 55.

The square root of 778272769 is about 27897.5405546797. The cubic root of 778272769 is about 919.8364426479.

The spelling of 778272769 in words is "seven hundred seventy-eight million, two hundred seventy-two thousand, seven hundred sixty-nine".