20021212001 has 32 divisors (see below), whose sum is σ = 24717788928. Its totient is φ = 15825438720.

The previous prime is 20021211989. The next prime is 20021212007. The reversal of 20021212001 is 10021212002.

It is a happy number.

It is not a de Polignac number, because 20021212001 - 2²² = 20017017697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20021212007) 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, 6008906 + ... + 6012236.

It is an arithmetic number, because the mean of its divisors is an integer number (772430904).

Almost surely, 2^20021212001 is an apocalyptic number.

It is an amenable number.

20021212001 is a deficient number, since it is larger than the sum of its proper divisors (4696576927).

20021212001 is a wasteful number, since it uses less digits than its factorization.

20021212001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4361.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20021212001 its reverse (10021212002), we get a palindrome (30042424003).

Subtracting from 20021212001 its reverse (10021212002), we obtain a palindrome (9999999999).

The spelling of 20021212001 in words is "twenty billion, twenty-one million, two hundred twelve thousand, one".