646378 has 8 divisors (see below), whose sum is σ = 982080. Its totient is φ = 319020.

The previous prime is 646339. The next prime is 646379. The reversal of 646378 is 873646.

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

It is not an unprimeable number, because it can be changed into a prime (646379) 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, 1888 + ... + 2203.

It is an arithmetic number, because the mean of its divisors is an integer number (122760).

2⁶⁴⁶³⁷⁸ is an apocalyptic number.

646378 is a deficient number, since it is larger than the sum of its proper divisors (335702).

646378 is a wasteful number, since it uses less digits than its factorization.

646378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4172.

The product of its digits is 24192, while the sum is 34.

The square root of 646378 is about 803.9763678119. The cubic root of 646378 is about 86.4627123861.

It can be divided in two parts, 646 and 378, that added together give a 10-th power (1024 = 2¹⁰).

The spelling of 646378 in words is "six hundred forty-six thousand, three hundred seventy-eight".