21424529 has 8 divisors (see below), whose sum is σ = 24514560. Its totient is φ = 18341856.

The previous prime is 21424511. The next prime is 21424547. The reversal of 21424529 is 92542412.

It is an interprime number because it is at equal distance from previous prime (21424511) and next prime (21424547).

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

It is a cyclic number.

It is not a de Polignac number, because 21424529 - 2¹² = 21420433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21424549) 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, 7757 + ... + 10149.

It is an arithmetic number, because the mean of its divisors is an integer number (3064320).

Almost surely, 2^21424529 is an apocalyptic number.

It is an amenable number.

21424529 is a deficient number, since it is larger than the sum of its proper divisors (3090031).

21424529 is a wasteful number, since it uses less digits than its factorization.

21424529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3679.

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

The square root of 21424529 is about 4628.6638460791. The cubic root of 21424529 is about 277.7391450925.

The spelling of 21424529 in words is "twenty-one million, four hundred twenty-four thousand, five hundred twenty-nine".