621369 has 18 divisors (see below), whose sum is σ = 1044810. Its totient is φ = 354816.

The previous prime is 621359. The next prime is 621371. The reversal of 621369 is 963126.

621369 = T₆₀ + T₆₁ + ... + T₁₅₇.

It is a happy number.

621369 is a `hidden beast` number, since 621 + 36 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 345744 + 275625 = 588^2 + 525^2 .

It is not a de Polignac number, because 621369 - 2⁴ = 621353 is a prime.

It is a super-2 number, since 2×621369² = 772198868322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (621359) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 264 + ... + 1145.

It is an arithmetic number, because the mean of its divisors is an integer number (58045).

2⁶²¹³⁶⁹ is an apocalyptic number.

It is an amenable number.

621369 is a deficient number, since it is larger than the sum of its proper divisors (423441).

621369 is a wasteful number, since it uses less digits than its factorization.

621369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1429 (or 1419 counting only the distinct ones).

The product of its digits is 1944, while the sum is 27.

The square root of 621369 is about 788.2696239232. The cubic root of 621369 is about 85.3329043897.

It can be divided in two parts, 621 and 369, that added together give a triangular number (990 = T₄₄).

The spelling of 621369 in words is "six hundred twenty-one thousand, three hundred sixty-nine".