21355405445 has 16 divisors (see below), whose sum is σ = 27978117120. Its totient is φ = 15519009600.

The previous prime is 21355405429. The next prime is 21355405453. The reversal of 21355405445 is 54450455312.

It is not a de Polignac number, because 21355405445 - 2⁴ = 21355405429 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21355405399 and 21355405408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81446 + ... + 222135.

It is an arithmetic number, because the mean of its divisors is an integer number (1748632320).

Almost surely, 2^21355405445 is an apocalyptic number.

It is an amenable number.

21355405445 is a deficient number, since it is larger than the sum of its proper divisors (6622711675).

21355405445 is a wasteful number, since it uses less digits than its factorization.

21355405445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304876.

The product of its (nonzero) digits is 240000, while the sum is 38.

The spelling of 21355405445 in words is "twenty-one billion, three hundred fifty-five million, four hundred five thousand, four hundred forty-five".