21330374555 has 32 divisors (see below), whose sum is σ = 31045762944. Its totient is φ = 13734199296.

The previous prime is 21330374551. The next prime is 21330374563. The reversal of 21330374555 is 55547303312.

It is a cyclic number.

It is not a de Polignac number, because 21330374555 - 2² = 21330374551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21330374551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 216239 + ... + 299031.

It is an arithmetic number, because the mean of its divisors is an integer number (970180092).

Almost surely, 2^21330374555 is an apocalyptic number.

21330374555 is a deficient number, since it is larger than the sum of its proper divisors (9715388389).

21330374555 is a wasteful number, since it uses less digits than its factorization.

21330374555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83255.

The product of its (nonzero) digits is 189000, while the sum is 38.

Adding to 21330374555 its reverse (55547303312), we get a palindrome (76877677867).

The spelling of 21330374555 in words is "twenty-one billion, three hundred thirty million, three hundred seventy-four thousand, five hundred fifty-five".