20819561057755 has 4 divisors (see below), whose sum is σ = 24983473269312. Its totient is φ = 16655648846200.

The previous prime is 20819561057749. The next prime is 20819561057761. The reversal of 20819561057755 is 55775016591802.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20819561057749) and next prime (20819561057761).

It is not a de Polignac number, because 20819561057755 - 2¹⁵ = 20819561024987 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20819561057693 and 20819561057702.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2081956105771 + ... + 2081956105780.

It is an arithmetic number, because the mean of its divisors is an integer number (6245868317328).

Almost surely, 2^{20819561057755} is an apocalyptic number.

20819561057755 is a deficient number, since it is larger than the sum of its proper divisors (4163912211557).

20819561057755 is an equidigital number, since it uses as much as digits as its factorization.

20819561057755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4163912211556.

The product of its (nonzero) digits is 26460000, while the sum is 61.

The spelling of 20819561057755 in words is "twenty trillion, eight hundred nineteen billion, five hundred sixty-one million, fifty-seven thousand, seven hundred fifty-five".