18421061 has 6 divisors (see below), whose sum is σ = 19080210. Its totient is φ = 17763536.

The previous prime is 18421057. The next prime is 18421093. The reversal of 18421061 is 16012481.

It can be written as a sum of positive squares in 3 ways, for example, as 2660161 + 15760900 = 1631^2 + 3970^2 .

It is not a de Polignac number, because 18421061 - 2² = 18421057 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18421961) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22715 + ... + 23511.

It is an arithmetic number, because the mean of its divisors is an integer number (3180035).

Almost surely, 2^18421061 is an apocalyptic number.

It is an amenable number.

18421061 is a deficient number, since it is larger than the sum of its proper divisors (659149).

18421061 is an frugal number, since it uses more digits than its factorization.

18421061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1623 (or 826 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 18421061 is about 4291.9763512862. The cubic root of 18421061 is about 264.1019129411.

The spelling of 18421061 in words is "eighteen million, four hundred twenty-one thousand, sixty-one".