21220142434201 has 4 divisors (see below), whose sum is σ = 21355302577252. Its totient is φ = 21084982291152.

The previous prime is 21220142434163. The next prime is 21220142434223. The reversal of 21220142434201 is 10243424102212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2507155560000 + 18712986874201 = 1583400^2 + 4325851^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220142434201 is a prime.

It is a super-2 number, since 2×21220142434201² (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 21220142434201.

It is not an unprimeable number, because it can be changed into a prime (21220142434301) 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, 67580071290 + ... + 67580071603.

It is an arithmetic number, because the mean of its divisors is an integer number (5338825644313).

Almost surely, 2^{21220142434201} is an apocalyptic number.

It is an amenable number.

21220142434201 is a deficient number, since it is larger than the sum of its proper divisors (135160143051).

21220142434201 is a wasteful number, since it uses less digits than its factorization.

21220142434201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135160143050.

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 21220142434201 its reverse (10243424102212), we get a palindrome (31463566536413).

The spelling of 21220142434201 in words is "twenty-one trillion, two hundred twenty billion, one hundred forty-two million, four hundred thirty-four thousand, two hundred one".