21254429 has 8 divisors (see below), whose sum is σ = 24389568. Its totient is φ = 18144000.

The previous prime is 21254417. The next prime is 21254447. The reversal of 21254429 is 92445212.

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

It is not a de Polignac number, because 21254429 - 2⁸ = 21254173 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21254459) 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, 4292 + ... + 7805.

It is an arithmetic number, because the mean of its divisors is an integer number (3048696).

Almost surely, 2^21254429 is an apocalyptic number.

It is an amenable number.

21254429 is a deficient number, since it is larger than the sum of its proper divisors (3135139).

21254429 is a wasteful number, since it uses less digits than its factorization.

21254429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12355.

The product of its digits is 5760, while the sum is 29.

The square root of 21254429 is about 4610.2525961166. The cubic root of 21254429 is about 277.0021547531.

The spelling of 21254429 in words is "twenty-one million, two hundred fifty-four thousand, four hundred twenty-nine".