21182045547 has 8 divisors (see below), whose sum is σ = 30415244944. Its totient is φ = 13035104928.

The previous prime is 21182045531. The next prime is 21182045551. The reversal of 21182045547 is 74554028112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21182045547 - 2⁴ = 21182045531 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 543129373 = 21182045547 / (2 + 1 + 1 + 8 + 2 + 0 + 4 + 5 + 5 + 4 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21182045567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 271564648 + ... + 271564725.

It is an arithmetic number, because the mean of its divisors is an integer number (3801905618).

Almost surely, 2^21182045547 is an apocalyptic number.

21182045547 is a deficient number, since it is larger than the sum of its proper divisors (9233199397).

21182045547 is a wasteful number, since it uses less digits than its factorization.

21182045547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543129389.

The product of its (nonzero) digits is 89600, while the sum is 39.

The spelling of 21182045547 in words is "twenty-one billion, one hundred eighty-two million, forty-five thousand, five hundred forty-seven".