20815455443455 has 16 divisors (see below), whose sum is σ = 25081194880224. Its totient is φ = 16584029130240.

The previous prime is 20815455443411. The next prime is 20815455443467. The reversal of 20815455443455 is 55434455451802.

It is not a de Polignac number, because 20815455443455 - 2¹⁹ = 20815454919167 is a prime.

It is a super-4 number, since 4×20815455443455⁴ (a number of 54 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20815455443396 and 20815455443405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4345461 + ... + 7779070.

It is an arithmetic number, because the mean of its divisors is an integer number (1567574680014).

Almost surely, 2^{20815455443455} is an apocalyptic number.

20815455443455 is a deficient number, since it is larger than the sum of its proper divisors (4265739436769).

20815455443455 is a wasteful number, since it uses less digits than its factorization.

20815455443455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12125946.

The product of its (nonzero) digits is 38400000, while the sum is 55.

The spelling of 20815455443455 in words is "twenty trillion, eight hundred fifteen billion, four hundred fifty-five million, four hundred forty-three thousand, four hundred fifty-five".