21054115 has 16 divisors (see below), whose sum is σ = 26724096. Its totient is φ = 15897600.

The previous prime is 21054067. The next prime is 21054119. The reversal of 21054115 is 51145012.

It is not a de Polignac number, because 21054115 - 2⁷ = 21053987 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21054092 and 21054101.

It is not an unprimeable number, because it can be changed into a prime (21054119) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4699 + ... + 8011.

It is an arithmetic number, because the mean of its divisors is an integer number (1670256).

Almost surely, 2^21054115 is an apocalyptic number.

21054115 is a deficient number, since it is larger than the sum of its proper divisors (5669981).

21054115 is a wasteful number, since it uses less digits than its factorization.

21054115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3390.

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 21054115 is about 4588.4763266252. The cubic root of 21054115 is about 276.1291971966.

Adding to 21054115 its reverse (51145012), we get a palindrome (72199127).

The spelling of 21054115 in words is "twenty-one million, fifty-four thousand, one hundred fifteen".