621361 has 4 divisors (see below), whose sum is σ = 669172. Its totient is φ = 573552.

The previous prime is 621359. The next prime is 621371. The reversal of 621361 is 163126.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 163126 = 2 ⋅81563.

It can be written as a sum of positive squares in 2 ways, for example, as 185761 + 435600 = 431^2 + 660^2 .

It is a cyclic number.

It is not a de Polignac number, because 621361 - 2¹ = 621359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621301) 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, 23886 + ... + 23911.

It is an arithmetic number, because the mean of its divisors is an integer number (167293).

2⁶²¹³⁶¹ is an apocalyptic number.

It is an amenable number.

621361 is a deficient number, since it is larger than the sum of its proper divisors (47811).

621361 is a wasteful number, since it uses less digits than its factorization.

621361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47810.

The product of its digits is 216, while the sum is 19.

The square root of 621361 is about 788.2645495010. The cubic root of 621361 is about 85.3325381735.

Adding to 621361 its reverse (163126), we get a palindrome (784487).

The spelling of 621361 in words is "six hundred twenty-one thousand, three hundred sixty-one".