1021121009 has 16 divisors (see below), whose sum is σ = 1095871680. Its totient is φ = 948657600.

The previous prime is 1021120987. The next prime is 1021121033. The reversal of 1021121009 is 9001211201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021121009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021121039) 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 15 ways as a sum of consecutive naturals, for example, 202847 + ... + 207819.

It is an arithmetic number, because the mean of its divisors is an integer number (68491980).

Almost surely, 2^1021121009 is an apocalyptic number.

1021121009 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1021121009 is a deficient number, since it is larger than the sum of its proper divisors (74750671).

1021121009 is a wasteful number, since it uses less digits than its factorization.

1021121009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5200.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 1021121009 is about 31954.9841026404. The cubic root of 1021121009 is about 1006.9913435392.

The spelling of 1021121009 in words is "one billion, twenty-one million, one hundred twenty-one thousand, nine".