21212020203401 has 16 divisors (see below), whose sum is σ = 21390968773440. Its totient is φ = 21033910272000.

The previous prime is 21212020203391. The next prime is 21212020203403. The reversal of 21212020203401 is 10430202021212.

It is a cyclic number.

It is not a de Polignac number, because 21212020203401 - 2⁶ = 21212020203337 is a prime.

It is a super-2 number, since 2×21212020203401² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212020203403) 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, 120346505 + ... + 120522633.

It is an arithmetic number, because the mean of its divisors is an integer number (1336935548340).

Almost surely, 2^{21212020203401} is an apocalyptic number.

It is an amenable number.

21212020203401 is a deficient number, since it is larger than the sum of its proper divisors (178948570039).

21212020203401 is a wasteful number, since it uses less digits than its factorization.

21212020203401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178504.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21212020203401 its reverse (10430202021212), we get a palindrome (31642222224613).

The spelling of 21212020203401 in words is "twenty-one trillion, two hundred twelve billion, twenty million, two hundred three thousand, four hundred one".