21254065 has 32 divisors (see below), whose sum is σ = 31703040. Its totient is φ = 13348800.

The previous prime is 21254041. The next prime is 21254069. The reversal of 21254065 is 56045212.

It is not a de Polignac number, because 21254065 - 2⁵ = 21254033 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21254069) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20100 + ... + 21130.

It is an arithmetic number, because the mean of its divisors is an integer number (990720).

Almost surely, 2^21254065 is an apocalyptic number.

It is an amenable number.

21254065 is a deficient number, since it is larger than the sum of its proper divisors (10448975).

21254065 is a wasteful number, since it uses less digits than its factorization.

21254065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1093.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 21254065 is about 4610.2131187180. The cubic root of 21254065 is about 277.0005734456. Note that the first 3 decimals are identical.

Adding to 21254065 its reverse (56045212), we get a palindrome (77299277).

The spelling of 21254065 in words is "twenty-one million, two hundred fifty-four thousand, sixty-five".