774840978 has 38 divisors (see below), whose sum is σ = 1743392199. Its totient is φ = 258280326.

The previous prime is 774840967. The next prime is 774841019. The reversal of 774840978 is 879048477.

774840978 is a `hidden beast` number, since 77 + 484 + 0 + 97 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 387420489 + 387420489 = 19683^2 + 19683^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=19683.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Leyland number of the form 9⁹ + 9⁹.

It is a nialpdrome in base 3 and base 9.

It is an unprimeable number.

It is a polite number, since it can be written in 18 ways as a sum of consecutive naturals, for example, 258280325 + 258280326 + 258280327.

Almost surely, 2^774840978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 774840978

774840978 is an abundant number, since it is smaller than the sum of its proper divisors (968551221).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

774840978 is an frugal number, since it uses more digits than its factorization.

774840978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56 (or 5 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 54.

The square root of 774840978 is about 27835.9655481896. The cubic root of 774840978 is about 918.4824453734.

774840978 divided by its sum of digits (54) gives a 15-th power (14348907 = 3¹⁵).

The spelling of 774840978 in words is "seven hundred seventy-four million, eight hundred forty thousand, nine hundred seventy-eight".