1021109090 has 16 divisors (see below), whose sum is σ = 1838385720. Its totient is φ = 408357120.

The previous prime is 1021109071. The next prime is 1021109101. The reversal of 1021109090 is 909011201.

It can be written as a sum of positive squares in 4 ways, for example, as 963667849 + 57441241 = 31043^2 + 7579^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 62276 + ... + 76944.

Almost surely, 2^1021109090 is an apocalyptic number.

1021109090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1021109090 is a deficient number, since it is larger than the sum of its proper divisors (817276630).

1021109090 is a wasteful number, since it uses less digits than its factorization.

1021109090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21637.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 1021109090 is about 31954.7976053675. The cubic root of 1021109090 is about 1006.9874254999.

The spelling of 1021109090 in words is "one billion, twenty-one million, one hundred nine thousand, ninety".