18905401 has 2 divisors, whose sum is σ = 18905402. Its totient is φ = 18905400.

The previous prime is 18905357. The next prime is 18905407. The reversal of 18905401 is 10450981.

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., 13838400 + 5067001 = 3720^2 + 2251^2 .

It is a cyclic number.

It is not a de Polignac number, because 18905401 - 2⁹ = 18904889 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18905401.

It is not a weakly prime, because it can be changed into another prime (18905407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9452700 + 9452701.

It is an arithmetic number, because the mean of its divisors is an integer number (9452701).

Almost surely, 2^18905401 is an apocalyptic number.

18905401 is the 1945-th centered decagonal number.

It is an amenable number.

18905401 is a deficient number, since it is larger than the sum of its proper divisors (1).

18905401 is an equidigital number, since it uses as much as digits as its factorization.

18905401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 18905401 is about 4348.0341534997. The cubic root of 18905401 is about 266.3965714899.

It can be divided in two parts, 18905 and 401, that added together give a triangular number (19306 = T₁₉₆).

The spelling of 18905401 in words is "eighteen million, nine hundred five thousand, four hundred one".