21426549 has 8 divisors (see below), whose sum is σ = 29490432. Its totient is φ = 13823520.

The previous prime is 21426541. The next prime is 21426553. The reversal of 21426549 is 94562412.

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

It is not a de Polignac number, because 21426549 - 2³ = 21426541 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 (21426541) 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, 115104 + ... + 115289.

It is an arithmetic number, because the mean of its divisors is an integer number (3686304).

Almost surely, 2^21426549 is an apocalyptic number.

It is an amenable number.

21426549 is a deficient number, since it is larger than the sum of its proper divisors (8063883).

21426549 is a wasteful number, since it uses less digits than its factorization.

21426549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230427.

The product of its digits is 17280, while the sum is 33.

The square root of 21426549 is about 4628.8820464557. The cubic root of 21426549 is about 277.7478736460.

The spelling of 21426549 in words is "twenty-one million, four hundred twenty-six thousand, five hundred forty-nine".