20445503381 has 2 divisors, whose sum is σ = 20445503382. Its totient is φ = 20445503380.

The previous prime is 20445503371. The next prime is 20445503383. The reversal of 20445503381 is 18330554402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14105362756 + 6340140625 = 118766^2 + 79625^2 .

It is a cyclic number.

It is not a de Polignac number, because 20445503381 - 2³⁰ = 19371761557 is a prime.

It is a super-2 number, since 2×20445503381² (a number of 21 digits) contains 22 as substring.

Together with 20445503383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20445503383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10222751690 + 10222751691.

It is an arithmetic number, because the mean of its divisors is an integer number (10222751691).

Almost surely, 2^20445503381 is an apocalyptic number.

It is an amenable number.

20445503381 is a deficient number, since it is larger than the sum of its proper divisors (1).

20445503381 is an equidigital number, since it uses as much as digits as its factorization.

20445503381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 57600, while the sum is 35.

The spelling of 20445503381 in words is "twenty billion, four hundred forty-five million, five hundred three thousand, three hundred eighty-one".