20101022009 has 2 divisors, whose sum is σ = 20101022010. Its totient is φ = 20101022008.

The previous prime is 20101021999. The next prime is 20101022069. The reversal of 20101022009 is 90022010102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13317852409 + 6783169600 = 115403^2 + 82360^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101022009 - 2¹² = 20101017913 is a prime.

It is not a weakly prime, because it can be changed into another prime (20101022069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050511004 + 10050511005.

It is an arithmetic number, because the mean of its divisors is an integer number (10050511005).

Almost surely, 2^20101022009 is an apocalyptic number.

It is an amenable number.

20101022009 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101022009 is an equidigital number, since it uses as much as digits as its factorization.

20101022009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The spelling of 20101022009 in words is "twenty billion, one hundred one million, twenty-two thousand, nine".