21054351 has 8 divisors (see below), whose sum is σ = 28172800. Its totient is φ = 13986072.

The previous prime is 21054343. The next prime is 21054353. The reversal of 21054351 is 15345012.

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

It is not a de Polignac number, because 21054351 - 2³ = 21054343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21054353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11551 + ... + 13248.

It is an arithmetic number, because the mean of its divisors is an integer number (3521600).

Almost surely, 2^21054351 is an apocalyptic number.

21054351 is a deficient number, since it is larger than the sum of its proper divisors (7118449).

21054351 is a wasteful number, since it uses less digits than its factorization.

21054351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25085.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21054351 is about 4588.5020431509. The cubic root of 21054351 is about 276.1302289228.

Adding to 21054351 its reverse (15345012), we get a palindrome (36399363).

The spelling of 21054351 in words is "twenty-one million, fifty-four thousand, three hundred fifty-one".