678120551 has 4 divisors (see below), whose sum is σ = 679325592. Its totient is φ = 676915512.

The previous prime is 678120539. The next prime is 678120577. The reversal of 678120551 is 155021876.

678120551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678120551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678120511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 601676 + ... + 602801.

It is an arithmetic number, because the mean of its divisors is an integer number (169831398).

Almost surely, 2^678120551 is an apocalyptic number.

678120551 is a deficient number, since it is larger than the sum of its proper divisors (1205041).

678120551 is a wasteful number, since it uses less digits than its factorization.

678120551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1205040.

The product of its (nonzero) digits is 16800, while the sum is 35.

The square root of 678120551 is about 26040.7478963259. The cubic root of 678120551 is about 878.5550283433. Note that the first 3 decimals are identical.

The spelling of 678120551 in words is "six hundred seventy-eight million, one hundred twenty thousand, five hundred fifty-one".