621913 has 2 divisors, whose sum is σ = 621914. Its totient is φ = 621912.

The previous prime is 621893. The next prime is 621923. The reversal of 621913 is 319126.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 394384 + 227529 = 628^2 + 477^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-621913 is a prime.

It is not a weakly prime, because it can be changed into another prime (621923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310956 + 310957.

It is an arithmetic number, because the mean of its divisors is an integer number (310957).

2⁶²¹⁹¹³ is an apocalyptic number.

It is an amenable number.

621913 is a deficient number, since it is larger than the sum of its proper divisors (1).

621913 is an equidigital number, since it uses as much as digits as its factorization.

621913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 324, while the sum is 22.

The square root of 621913 is about 788.6146080311. The cubic root of 621913 is about 85.3577997200.

The spelling of 621913 in words is "six hundred twenty-one thousand, nine hundred thirteen".