2558397978 has 24 divisors (see below), whose sum is σ = 5551841568. Its totient is φ = 851469192.

The previous prime is 2558397811. The next prime is 2558397979. The reversal of 2558397978 is 8797938552.

2558397978 is a `hidden beast` number, since 2 + 558 + 3 + 9 + 7 + 9 + 78 = 666.

It is not an unprimeable number, because it can be changed into a prime (2558397979) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 98950 + ... + 122097.

It is an arithmetic number, because the mean of its divisors is an integer number (231326732).

Almost surely, 2^2558397978 is an apocalyptic number.

2558397978 is an abundant number, since it is smaller than the sum of its proper divisors (2993443590).

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

2558397978 is a wasteful number, since it uses less digits than its factorization.

2558397978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221698 (or 221695 counting only the distinct ones).

The product of its digits is 38102400, while the sum is 63.

The square root of 2558397978 is about 50580.6087151984. The cubic root of 2558397978 is about 1367.6953416415.

The spelling of 2558397978 in words is "two billion, five hundred fifty-eight million, three hundred ninety-seven thousand, nine hundred seventy-eight".