21546334004451 has 8 divisors (see below), whose sum is σ = 28730202603600. Its totient is φ = 14363344037472.

The previous prime is 21546334004407. The next prime is 21546334004453. The reversal of 21546334004451 is 15440043364512.

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

It is not a de Polignac number, because 21546334004451 - 2⁹ = 21546334003939 is a prime.

It is a super-2 number, since 2×21546334004451² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21546334004453) 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, 219600820 + ... + 219698913.

It is an arithmetic number, because the mean of its divisors is an integer number (3591275325450).

Almost surely, 2^{21546334004451} is an apocalyptic number.

21546334004451 is a deficient number, since it is larger than the sum of its proper divisors (7183868599149).

21546334004451 is a wasteful number, since it uses less digits than its factorization.

21546334004451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439316085.

The product of its (nonzero) digits is 691200, while the sum is 42.

Adding to 21546334004451 its reverse (15440043364512), we get a palindrome (36986377368963).

The spelling of 21546334004451 in words is "twenty-one trillion, five hundred forty-six billion, three hundred thirty-four million, four thousand, four hundred fifty-one".