678550401 has 27 divisors (see below), whose sum is σ = 1036697571. Its totient is φ = 427620384.

The previous prime is 678550391. The next prime is 678550417. The reversal of 678550401 is 104055876.

The square root of 678550401 is 26049.

It is a perfect power (a square), and thus also a powerful number.

678550401 is a `hidden beast` number, since 67 + 8 + 550 + 40 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 586850625 + 91699776 = 24225^2 + 9576^2 .

It is not a de Polignac number, because 678550401 - 2⁷ = 678550273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (678550441) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1484565 + ... + 1485021.

Almost surely, 2^678550401 is an apocalyptic number.

678550401 is the 26049-th square number.

678550401 is the 13025-th centered octagonal number.

It is an amenable number.

678550401 is a deficient number, since it is larger than the sum of its proper divisors (358147170).

678550401 is an equidigital number, since it uses as much as digits as its factorization.

678550401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The cubic root of 678550401 is about 878.7406232260.

Multiplying 678550401 by its sum of digits (36), we get a square (24427814436 = 156294²).

The spelling of 678550401 in words is "six hundred seventy-eight million, five hundred fifty thousand, four hundred one".