621101 has 4 divisors (see below), whose sum is σ = 668892. Its totient is φ = 573312.

The previous prime is 621097. The next prime is 621113. The reversal of 621101 is 101126.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 249001 + 372100 = 499^2 + 610^2 .

It is a cyclic number.

It is not a de Polignac number, because 621101 - 2² = 621097 is a prime.

It is a Duffinian number.

It is a congruent 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, 23876 + ... + 23901.

It is an arithmetic number, because the mean of its divisors is an integer number (167223).

2⁶²¹¹⁰¹ is an apocalyptic number.

It is an amenable number.

621101 is a deficient number, since it is larger than the sum of its proper divisors (47791).

621101 is a wasteful number, since it uses less digits than its factorization.

621101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47790.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 621101 is about 788.0996129932. The cubic root of 621101 is about 85.3206344357.

Adding to 621101 its reverse (101126), we get a palindrome (722227).

The spelling of 621101 in words is "six hundred twenty-one thousand, one hundred one".