20621233104361 has 2 divisors, whose sum is σ = 20621233104362. Its totient is φ = 20621233104360.

The previous prime is 20621233104359. The next prime is 20621233104397. The reversal of 20621233104361 is 16340133212602.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20348498486761 + 272734617600 = 4510931^2 + 522240^2 .

It is a cyclic number.

It is not a de Polignac number, because 20621233104361 - 2¹ = 20621233104359 is a prime.

Together with 20621233104359, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20621233144361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10310616552180 + 10310616552181.

It is an arithmetic number, because the mean of its divisors is an integer number (10310616552181).

Almost surely, 2^{20621233104361} is an apocalyptic number.

It is an amenable number.

20621233104361 is a deficient number, since it is larger than the sum of its proper divisors (1).

20621233104361 is an equidigital number, since it uses as much as digits as its factorization.

20621233104361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 34.

Adding to 20621233104361 its reverse (16340133212602), we get a palindrome (36961366316963).

The spelling of 20621233104361 in words is "twenty trillion, six hundred twenty-one billion, two hundred thirty-three million, one hundred four thousand, three hundred sixty-one".