20619857643265 has 24 divisors (see below), whose sum is σ = 27668386690560. Its totient is φ = 14708406175488.

The previous prime is 20619857643247. The next prime is 20619857643271. The reversal of 20619857643265 is 56234675891602.

It is a happy number.

It is not a de Polignac number, because 20619857643265 - 2⁷ = 20619857643137 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20619857643197 and 20619857643206.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 375493537 + ... + 375548446.

It is an arithmetic number, because the mean of its divisors is an integer number (1152849445440).

It is a 2-persistent number, because it is pandigital, and so is 2⋅20619857643265 = 41239715286530, but 3⋅20619857643265 = 61859572929795 is not.

Almost surely, 2^{20619857643265} is an apocalyptic number.

It is an amenable number.

20619857643265 is a deficient number, since it is larger than the sum of its proper divisors (7048529047295).

20619857643265 is a wasteful number, since it uses less digits than its factorization.

20619857643265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 751042041 (or 751042024 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 64.

The spelling of 20619857643265 in words is "twenty trillion, six hundred nineteen billion, eight hundred fifty-seven million, six hundred forty-three thousand, two hundred sixty-five".