978455857 has 24 divisors (see below), whose sum is σ = 1057712040. Its totient is φ = 904485120.

The previous prime is 978455833. The next prime is 978455869. The reversal of 978455857 is 758554879.

It can be written as a sum of positive squares in 4 ways, for example, as 398561296 + 579894561 = 19964^2 + 24081^2 .

It is not a de Polignac number, because 978455857 - 2¹⁹ = 977931569 is a prime.

Its product of digits (14112000) is a multiple of the sum of its prime divisors (490).

It is not an unprimeable number, because it can be changed into a prime (978455827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4272619 + ... + 4272847.

It is an arithmetic number, because the mean of its divisors is an integer number (44071335).

Almost surely, 2^978455857 is an apocalyptic number.

It is an amenable number.

978455857 is a deficient number, since it is larger than the sum of its proper divisors (79256183).

978455857 is a wasteful number, since it uses less digits than its factorization.

978455857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513 (or 490 counting only the distinct ones).

The product of its digits is 14112000, while the sum is 58.

The square root of 978455857 is about 31280.2790428730. The cubic root of 978455857 is about 992.7664204924.

The spelling of 978455857 in words is "nine hundred seventy-eight million, four hundred fifty-five thousand, eight hundred fifty-seven".