105989621 has 2 divisors, whose sum is σ = 105989622. Its totient is φ = 105989620.

The previous prime is 105989573. The next prime is 105989623. The reversal of 105989621 is 126989501.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103754596 + 2235025 = 10186^2 + 1495^2 .

It is an emirp because it is prime and its reverse (126989501) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 105989621 - 2¹⁴ = 105973237 is a prime.

It is a super-2 number, since 2×105989621² = 22467599519447282, which contains 22 as substring.

Together with 105989623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (105989623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52994810 + 52994811.

It is an arithmetic number, because the mean of its divisors is an integer number (52994811).

Almost surely, 2^105989621 is an apocalyptic number.

It is an amenable number.

105989621 is a deficient number, since it is larger than the sum of its proper divisors (1).

105989621 is an equidigital number, since it uses as much as digits as its factorization.

105989621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 105989621 is about 10295.1260798496. The cubic root of 105989621 is about 473.2469021030.

The spelling of 105989621 in words is "one hundred five million, nine hundred eighty-nine thousand, six hundred twenty-one".