20019995845641 has 81 divisors (see below), whose sum is σ = 32589673253319. Its totient is φ = 11833816420800.

The previous prime is 20019995845607. The next prime is 20019995845673. The reversal of 20019995845641 is 14654859991002.

The square root of 20019995845641 is 4474371.

It is a perfect power (a square), and thus also a powerful number.

20019995845641 is a `hidden beast` number, since 2 + 0 + 0 + 1 + 9 + 9 + 9 + 584 + 5 + 6 + 41 = 666.

It can be written as a sum of positive squares in only one way, i.e., 964675588041 + 19055320257600 = 982179^2 + 4365240^2 .

It is not a de Polignac number, because 20019995845641 - 2³⁷ = 19882556892169 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20019995843641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 6053822310 + ... + 6053825616.

Almost surely, 2^{20019995845641} is an apocalyptic number.

20019995845641 is the 4474371-st square number.

20019995845641 is the 2237186-th centered octagonal number.

It is an amenable number.

20019995845641 is a deficient number, since it is larger than the sum of its proper divisors (12569677407678).

20019995845641 is an frugal number, since it uses more digits than its factorization.

20019995845641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6724 (or 3362 counting only the distinct ones).

The product of its (nonzero) digits is 27993600, while the sum is 63.

The spelling of 20019995845641 in words is "twenty trillion, nineteen billion, nine hundred ninety-five million, eight hundred forty-five thousand, six hundred forty-one".