646427851 has 8 divisors (see below), whose sum is σ = 664872624. Its totient is φ = 628034400.

The previous prime is 646427843. The next prime is 646427911. The reversal of 646427851 is 158724646.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 646427851 - 2³ = 646427843 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646427798 and 646427807.

It is not an unprimeable number, because it can be changed into a prime (646427051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13476 + ... + 38398.

It is an arithmetic number, because the mean of its divisors is an integer number (83109078).

Almost surely, 2^646427851 is an apocalyptic number.

646427851 is a deficient number, since it is larger than the sum of its proper divisors (18444773).

646427851 is a wasteful number, since it uses less digits than its factorization.

646427851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25661.

The product of its digits is 322560, while the sum is 43.

The square root of 646427851 is about 25424.9454473358. The cubic root of 646427851 is about 864.6493510088.

The spelling of 646427851 in words is "six hundred forty-six million, four hundred twenty-seven thousand, eight hundred fifty-one".