20640331254133 has 4 divisors (see below), whose sum is σ = 20647311416460. Its totient is φ = 20633351091808.

The previous prime is 20640331254121. The next prime is 20640331254139. The reversal of 20640331254133 is 33145213304602.

It is a happy number.

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 11825744344164 + 8814586909969 = 3438858^2 + 2968937^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20640331254133 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20640331254092 and 20640331254101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20640331254139) 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, 3490076728 + ... + 3490082641.

It is an arithmetic number, because the mean of its divisors is an integer number (5161827854115).

Almost surely, 2^{20640331254133} is an apocalyptic number.

It is an amenable number.

20640331254133 is a deficient number, since it is larger than the sum of its proper divisors (6980162327).

20640331254133 is an equidigital number, since it uses as much as digits as its factorization.

20640331254133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6980162326.

The product of its (nonzero) digits is 155520, while the sum is 37.

Adding to 20640331254133 its reverse (33145213304602), we get a palindrome (53785544558735).

The spelling of 20640331254133 in words is "twenty trillion, six hundred forty billion, three hundred thirty-one million, two hundred fifty-four thousand, one hundred thirty-three".