105556621 has 4 divisors (see below), whose sum is σ = 111765852. Its totient is φ = 99347392.

The previous prime is 105556603. The next prime is 105556663. The reversal of 105556621 is 126655501.

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 40576900 + 64979721 = 6370^2 + 8061^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-105556621 is a prime.

It is a super-2 number, since 2×105556621² = 22284400473875282, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105556601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3104590 + ... + 3104623.

It is an arithmetic number, because the mean of its divisors is an integer number (27941463).

Almost surely, 2^105556621 is an apocalyptic number.

It is an amenable number.

105556621 is a deficient number, since it is larger than the sum of its proper divisors (6209231).

105556621 is an equidigital number, since it uses as much as digits as its factorization.

105556621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6209230.

The product of its (nonzero) digits is 9000, while the sum is 31.

The square root of 105556621 is about 10274.0751895244. The cubic root of 105556621 is about 472.6015697589.

The spelling of 105556621 in words is "one hundred five million, five hundred fifty-six thousand, six hundred twenty-one".