21005141451 has 8 divisors (see below), whose sum is σ = 32007834624. Its totient is φ = 12002937960.

The previous prime is 21005141449. The next prime is 21005141471. The reversal of 21005141451 is 15414150012.

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

It is not a de Polignac number, because 21005141451 - 2¹ = 21005141449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21005141411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 500122395 + ... + 500122436.

It is an arithmetic number, because the mean of its divisors is an integer number (4000979328).

Almost surely, 2^21005141451 is an apocalyptic number.

21005141451 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21005141451 is a deficient number, since it is larger than the sum of its proper divisors (11002693173).

21005141451 is a wasteful number, since it uses less digits than its factorization.

21005141451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000244841.

The product of its (nonzero) digits is 800, while the sum is 24.

Adding to 21005141451 its reverse (15414150012), we get a palindrome (36419291463).

The spelling of 21005141451 in words is "twenty-one billion, five million, one hundred forty-one thousand, four hundred fifty-one".