20011210121 has 4 divisors (see below), whose sum is σ = 22869954432. Its totient is φ = 17152465812.

The previous prime is 20011210091. The next prime is 20011210123. The reversal of 20011210121 is 12101211002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20011210121 - 2⁶ = 20011210057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20011210123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1429372145 + ... + 1429372158.

It is an arithmetic number, because the mean of its divisors is an integer number (5717488608).

Almost surely, 2^20011210121 is an apocalyptic number.

It is an amenable number.

20011210121 is a deficient number, since it is larger than the sum of its proper divisors (2858744311).

20011210121 is an equidigital number, since it uses as much as digits as its factorization.

20011210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2858744310.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 20011210121 its reverse (12101211002), we get a palindrome (32112421123).

The spelling of 20011210121 in words is "twenty billion, eleven million, two hundred ten thousand, one hundred twenty-one".