646380 has 144 divisors (see below), whose sum is σ = 2446080. Its totient is φ = 139968.

The previous prime is 646379. The next prime is 646397. The reversal of 646380 is 83646.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 34011 + ... + 34029.

2⁶⁴⁶³⁸⁰ is an apocalyptic number.

646380 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1223040).

646380 is an abundant number, since it is smaller than the sum of its proper divisors (1799700).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646380 is a wasteful number, since it uses less digits than its factorization.

646380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 646380 is about 803.9776116286. The cubic root of 646380 is about 86.4628015626.

The spelling of 646380 in words is "six hundred forty-six thousand, three hundred eighty".