10121221009 has 32 divisors (see below), whose sum is σ = 10906721280. Its totient is φ = 9374400000.

The previous prime is 10121221003. The next prime is 10121221013. The reversal of 10121221009 is 90012212101.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 10121221009 - 2¹³ = 10121212817 is a prime.

It is a super-2 number, since 2×10121221009² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10121221003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32543964 + ... + 32544274.

It is an arithmetic number, because the mean of its divisors is an integer number (340835040).

Almost surely, 2^10121221009 is an apocalyptic number.

It is an amenable number.

10121221009 is a deficient number, since it is larger than the sum of its proper divisors (785500271).

10121221009 is a wasteful number, since it uses less digits than its factorization.

10121221009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 753.

The product of its (nonzero) digits is 72, while the sum is 19.

It can be divided in two parts, 101212 and 21009, that added together give a palindrome (122221).

The spelling of 10121221009 in words is "ten billion, one hundred twenty-one million, two hundred twenty-one thousand, nine".