21440215334451 has 8 divisors (see below), whose sum is σ = 28593191404800. Its totient is φ = 14290358076872.

The previous prime is 21440215334441. The next prime is 21440215334471. The reversal of 21440215334451 is 15443351204412.

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

It is a cyclic number.

It is not a de Polignac number, because 21440215334451 - 2¹⁸ = 21440215072307 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21440215334401) 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, 779687151 + ... + 779714648.

It is an arithmetic number, because the mean of its divisors is an integer number (3574148925600).

Almost surely, 2^{21440215334451} is an apocalyptic number.

21440215334451 is a deficient number, since it is larger than the sum of its proper divisors (7152976070349).

21440215334451 is a wasteful number, since it uses less digits than its factorization.

21440215334451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1559406385.

The product of its (nonzero) digits is 230400, while the sum is 39.

Adding to 21440215334451 its reverse (15443351204412), we get a palindrome (36883566538863).

The spelling of 21440215334451 in words is "twenty-one trillion, four hundred forty billion, two hundred fifteen million, three hundred thirty-four thousand, four hundred fifty-one".