919621 has 2 divisors, whose sum is σ = 919622. Its totient is φ = 919620.

The previous prime is 919613. The next prime is 919631. The reversal of 919621 is 126919.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 748225 + 171396 = 865^2 + 414^2 .

It is a cyclic number.

It is not a de Polignac number, because 919621 - 2³ = 919613 is a prime.

It is a super-3 number, since 3×919621³ = 2333178118784160183, which contains 333 as substring.

It is a Chen prime.

919621 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 919621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (919631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459810 + 459811.

It is an arithmetic number, because the mean of its divisors is an integer number (459811).

2⁹¹⁹⁶²¹ is an apocalyptic number.

It is an amenable number.

919621 is a deficient number, since it is larger than the sum of its proper divisors (1).

919621 is an equidigital number, since it uses as much as digits as its factorization.

919621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972, while the sum is 28.

The square root of 919621 is about 958.9687169037. The cubic root of 919621 is about 97.2455253105.

It can be divided in two parts, 919 and 621, that added together give a triangular number (1540 = T₅₅).

The spelling of 919621 in words is "nine hundred nineteen thousand, six hundred twenty-one".