1021091020 has 24 divisors (see below), whose sum is σ = 2213463168. Its totient is φ = 395260800.

The previous prime is 1021090997. The next prime is 1021091023. The reversal of 1021091020 is 201901201.

It is a super-2 number, since 2×1021091020² = 2085253742249280800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1021090985 and 1021091003.

It is not an unprimeable number, because it can be changed into a prime (1021091023) 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 7 ways as a sum of consecutive naturals, for example, 822841 + ... + 824080.

It is an arithmetic number, because the mean of its divisors is an integer number (92227632).

Almost surely, 2^1021091020 is an apocalyptic number.

1021091020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021091020 is an abundant number, since it is smaller than the sum of its proper divisors (1192372148).

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

1021091020 is a wasteful number, since it uses less digits than its factorization.

1021091020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1646961 (or 1646959 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 1021091020 is about 31954.5148609707. The cubic root of 1021091020 is about 1006.9814854326.

Adding to 1021091020 its reverse (201901201), we get a palindrome (1222992221).

The spelling of 1021091020 in words is "one billion, twenty-one million, ninety-one thousand, twenty".