621678 has 8 divisors (see below), whose sum is σ = 1243368. Its totient is φ = 207224.

The previous prime is 621671. The next prime is 621679. The reversal of 621678 is 876126.

It is a happy number.

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

621678 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621671) 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, 51801 + ... + 51812.

It is an arithmetic number, because the mean of its divisors is an integer number (155421).

2⁶²¹⁶⁷⁸ is an apocalyptic number.

621678 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

621678 is a wasteful number, since it uses less digits than its factorization.

621678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103618.

The product of its digits is 4032, while the sum is 30.

The square root of 621678 is about 788.4655984886. The cubic root of 621678 is about 85.3470470853.

The spelling of 621678 in words is "six hundred twenty-one thousand, six hundred seventy-eight".