18420742085 has 16 divisors (see below), whose sum is σ = 22437190512. Its totient is φ = 14516544000.

The previous prime is 18420742061. The next prime is 18420742091. The reversal of 18420742085 is 58024702481.

It can be written as a sum of positive squares in 8 ways, for example, as 3525271876 + 14895470209 = 59374^2 + 122047^2 .

It is not a de Polignac number, because 18420742085 - 2²² = 18416547781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6905 + ... + 192065.

It is an arithmetic number, because the mean of its divisors is an integer number (1402324407).

Almost surely, 2^18420742085 is an apocalyptic number.

It is an amenable number.

18420742085 is a deficient number, since it is larger than the sum of its proper divisors (4016448427).

18420742085 is a wasteful number, since it uses less digits than its factorization.

18420742085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185464.

The product of its (nonzero) digits is 143360, while the sum is 41.

The spelling of 18420742085 in words is "eighteen billion, four hundred twenty million, seven hundred forty-two thousand, eighty-five".