621541 has 2 divisors, whose sum is σ = 621542. Its totient is φ = 621540.

The previous prime is 621527. The next prime is 621583. The reversal of 621541 is 145126.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 556516 + 65025 = 746^2 + 255^2 .

It is a cyclic number.

It is not a de Polignac number, because 621541 - 2⁹ = 621029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310770 + 310771.

It is an arithmetic number, because the mean of its divisors is an integer number (310771).

2⁶²¹⁵⁴¹ is an apocalyptic number.

It is an amenable number.

621541 is a deficient number, since it is larger than the sum of its proper divisors (1).

621541 is an equidigital number, since it uses as much as digits as its factorization.

621541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 240, while the sum is 19.

The square root of 621541 is about 788.3787161003. The cubic root of 621541 is about 85.3407772776.

Adding to 621541 its reverse (145126), we get a palindrome (766667).

The spelling of 621541 in words is "six hundred twenty-one thousand, five hundred forty-one".