21420203342401 has 8 divisors (see below), whose sum is σ = 22314556605600. Its totient is φ = 20543560044960.

The previous prime is 21420203342399. The next prime is 21420203342407. The reversal of 21420203342401 is 10424330202412.

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

It is a cyclic number.

It is not a de Polignac number, because 21420203342401 - 2¹ = 21420203342399 is a prime.

It is a super-2 number, since 2×21420203342401² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21420203342401.

It is not an unprimeable number, because it can be changed into a prime (21420203342407) 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, 4427488971 + ... + 4427493808.

It is an arithmetic number, because the mean of its divisors is an integer number (2789319575700).

Almost surely, 2^{21420203342401} is an apocalyptic number.

It is an amenable number.

21420203342401 is a deficient number, since it is larger than the sum of its proper divisors (894353263199).

21420203342401 is an equidigital number, since it uses as much as digits as its factorization.

21420203342401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8854982879.

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 21420203342401 its reverse (10424330202412), we get a palindrome (31844533544813).

The spelling of 21420203342401 in words is "twenty-one trillion, four hundred twenty billion, two hundred three million, three hundred forty-two thousand, four hundred one".