621388 has 12 divisors (see below), whose sum is σ = 1106280. Its totient is φ = 305312.

The previous prime is 621371. The next prime is 621389. The reversal of 621388 is 883126.

It is a super-2 number, since 2×621388² = 772246093088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (621389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1081 + ... + 1552.

It is an arithmetic number, because the mean of its divisors is an integer number (92190).

2⁶²¹³⁸⁸ is an apocalyptic number.

It is an amenable number.

621388 is a deficient number, since it is larger than the sum of its proper divisors (484892).

621388 is a wasteful number, since it uses less digits than its factorization.

621388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2696 (or 2694 counting only the distinct ones).

The product of its digits is 2304, while the sum is 28.

The square root of 621388 is about 788.2816755450. The cubic root of 621388 is about 85.3337741405. Note that the first 3 decimals are identical.

The spelling of 621388 in words is "six hundred twenty-one thousand, three hundred eighty-eight".