20121000001 has 16 divisors (see below), whose sum is σ = 21736364544. Its totient is φ = 18578571264.

The previous prime is 20120999993. The next prime is 20121000013. The reversal of 20121000001 is 10000012102.

It is not a de Polignac number, because 20121000001 - 2³ = 20120999993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20121000061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48576 + ... + 206401.

It is an arithmetic number, because the mean of its divisors is an integer number (1358522784).

Almost surely, 2^20121000001 is an apocalyptic number.

It is an amenable number.

20121000001 is a deficient number, since it is larger than the sum of its proper divisors (1615364543).

20121000001 is a wasteful number, since it uses less digits than its factorization.

20121000001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255120.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 20121000001 its reverse (10000012102), we get a palindrome (30121012103).

The spelling of 20121000001 in words is "twenty billion, one hundred twenty-one million, one", and thus it is an aban number.