1021805118 has 40 divisors (see below), whose sum is σ = 2318611680. Its totient is φ = 336286080.

The previous prime is 1021805003. The next prime is 1021805119. The reversal of 1021805118 is 8115081201.

It is a super-3 number, since 3×1021805118³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 1021805091 and 1021805100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021805119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 27123 + ... + 52718.

It is an arithmetic number, because the mean of its divisors is an integer number (57965292).

Almost surely, 2^1021805118 is an apocalyptic number.

1021805118 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1021805118 is an abundant number, since it is smaller than the sum of its proper divisors (1296806562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1021805118 is an equidigital number, since it uses as much as digits as its factorization.

1021805118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79934 (or 79925 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 27.

The square root of 1021805118 is about 31965.6865716975. The cubic root of 1021805118 is about 1007.2161742397.

Adding to 1021805118 its reverse (8115081201), we get a palindrome (9136886319).

The spelling of 1021805118 in words is "one billion, twenty-one million, eight hundred five thousand, one hundred eighteen".