21012120201 has 32 divisors (see below), whose sum is σ = 29319413760. Its totient is φ = 13368204864.

The previous prime is 21012120149. The next prime is 21012120203. The reversal of 21012120201 is 10202121012.

It is a de Polignac number, because none of the positive numbers 2^k-21012120201 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21012120203) 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, 5437396 + ... + 5441258.

It is an arithmetic number, because the mean of its divisors is an integer number (916231680).

Almost surely, 2^21012120201 is an apocalyptic number.

It is an amenable number.

21012120201 is a deficient number, since it is larger than the sum of its proper divisors (8307293559).

21012120201 is a wasteful number, since it uses less digits than its factorization.

21012120201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4605.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21012120201 its reverse (10202121012), we get a palindrome (31214241213).

The spelling of 21012120201 in words is "twenty-one billion, twelve million, one hundred twenty thousand, two hundred one".