626561 has 4 divisors (see below), whose sum is σ = 674772. Its totient is φ = 578352.

The previous prime is 626539. The next prime is 626581. The reversal of 626561 is 165626.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165626 = 2 ⋅82813.

It can be written as a sum of positive squares in 2 ways, for example, as 295936 + 330625 = 544^2 + 575^2 .

It is a cyclic number.

It is not a de Polignac number, because 626561 - 2¹⁸ = 364417 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 626561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (626581) 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, 24086 + ... + 24111.

It is an arithmetic number, because the mean of its divisors is an integer number (168693).

2⁶²⁶⁵⁶¹ is an apocalyptic number.

It is an amenable number.

626561 is a deficient number, since it is larger than the sum of its proper divisors (48211).

626561 is a wasteful number, since it uses less digits than its factorization.

626561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48210.

The product of its digits is 2160, while the sum is 26.

The square root of 626561 is about 791.5560624491. The cubic root of 626561 is about 85.5699187544.

The spelling of 626561 in words is "six hundred twenty-six thousand, five hundred sixty-one".