621901 has 4 divisors (see below), whose sum is σ = 710752. Its totient is φ = 533052.

The previous prime is 621893. The next prime is 621913. The reversal of 621901 is 109126.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 109126 = 2 ⋅54563.

It is a cyclic number.

It is not a de Polignac number, because 621901 - 2³ = 621893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44415 + ... + 44428.

It is an arithmetic number, because the mean of its divisors is an integer number (177688).

2⁶²¹⁹⁰¹ is an apocalyptic number.

It is an amenable number.

621901 is a deficient number, since it is larger than the sum of its proper divisors (88851).

621901 is an equidigital number, since it uses as much as digits as its factorization.

621901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88850.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 621901 is about 788.6069997153. The cubic root of 621901 is about 85.3572507149.

The spelling of 621901 in words is "six hundred twenty-one thousand, nine hundred one".