678821401 has 4 divisors (see below), whose sum is σ = 679871232. Its totient is φ = 677771572.

The previous prime is 678821389. The next prime is 678821413. The reversal of 678821401 is 104128876.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (678821389) and next prime (678821413).

It is a cyclic number.

It is not a de Polignac number, because 678821401 - 2⁵ = 678821369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678821201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 523945 + ... + 525238.

It is an arithmetic number, because the mean of its divisors is an integer number (169967808).

Almost surely, 2^678821401 is an apocalyptic number.

It is an amenable number.

678821401 is a deficient number, since it is larger than the sum of its proper divisors (1049831).

678821401 is a wasteful number, since it uses less digits than its factorization.

678821401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049830.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 678821401 is about 26054.2012159268. The cubic root of 678821401 is about 878.8575916992.

The spelling of 678821401 in words is "six hundred seventy-eight million, eight hundred twenty-one thousand, four hundred one".