20645854633 has 2 divisors, whose sum is σ = 20645854634. Its totient is φ = 20645854632.

The previous prime is 20645854571. The next prime is 20645854681. The reversal of 20645854633 is 33645854602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20594546064 + 51308569 = 143508^2 + 7163^2 .

It is a cyclic number.

It is not a de Polignac number, because 20645854633 - 2²¹ = 20643757481 is a prime.

It is not a weakly prime, because it can be changed into another prime (20645854133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10322927316 + 10322927317.

It is an arithmetic number, because the mean of its divisors is an integer number (10322927317).

Almost surely, 2^20645854633 is an apocalyptic number.

It is an amenable number.

20645854633 is a deficient number, since it is larger than the sum of its proper divisors (1).

20645854633 is an equidigital number, since it uses as much as digits as its factorization.

20645854633 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2073600, while the sum is 46.

The spelling of 20645854633 in words is "twenty billion, six hundred forty-five million, eight hundred fifty-four thousand, six hundred thirty-three".