20121212021 has 8 divisors (see below), whose sum is σ = 21389930400. Its totient is φ = 18873464400.

The previous prime is 20121212011. The next prime is 20121212099. The reversal of 20121212021 is 12021212102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20121212021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20121211987 and 20121212005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121212011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5240711 + ... + 5244548.

It is an arithmetic number, because the mean of its divisors is an integer number (2673741300).

Almost surely, 2^20121212021 is an apocalyptic number.

It is an amenable number.

20121212021 is a deficient number, since it is larger than the sum of its proper divisors (1268718379).

20121212021 is a wasteful number, since it uses less digits than its factorization.

20121212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10485379.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 20121212021 its reverse (12021212102), we get a palindrome (32142424123).

The spelling of 20121212021 in words is "twenty billion, one hundred twenty-one million, two hundred twelve thousand, twenty-one".