21355315443 has 32 divisors (see below), whose sum is σ = 39444165120. Its totient is φ = 11093669280.

The previous prime is 21355315403. The next prime is 21355315477. The reversal of 21355315443 is 34451355312.

21355315443 is a `hidden beast` number, since 2 + 1 + 35 + 531 + 54 + 43 = 666.

It is not a de Polignac number, because 21355315443 - 2²¹ = 21353218291 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21355315398 and 21355315407.

It is not an unprimeable number, because it can be changed into a prime (21355315403) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5133880 + ... + 5138037.

It is an arithmetic number, because the mean of its divisors is an integer number (1232630160).

Almost surely, 2^21355315443 is an apocalyptic number.

21355315443 is a deficient number, since it is larger than the sum of its proper divisors (18088849677).

21355315443 is a wasteful number, since it uses less digits than its factorization.

21355315443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10271944 (or 10271938 counting only the distinct ones).

The product of its digits is 108000, while the sum is 36.

The spelling of 21355315443 in words is "twenty-one billion, three hundred fifty-five million, three hundred fifteen thousand, four hundred forty-three".