21477849 has 8 divisors (see below), whose sum is σ = 28678272. Its totient is φ = 14298000.

The previous prime is 21477811. The next prime is 21477853. The reversal of 21477849 is 94877412.

It is a happy number.

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

It is not a de Polignac number, because 21477849 - 2¹⁷ = 21346777 is a prime.

It is a super-2 number, since 2×21477849² = 922595995333602, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21477849.

It is not an unprimeable number, because it can be changed into a prime (21477889) 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, 2514 + ... + 7019.

It is an arithmetic number, because the mean of its divisors is an integer number (3584784).

Almost surely, 2^21477849 is an apocalyptic number.

It is an amenable number.

21477849 is a deficient number, since it is larger than the sum of its proper divisors (7200423).

21477849 is an equidigital number, since it uses as much as digits as its factorization.

21477849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10287.

The product of its digits is 112896, while the sum is 42.

The square root of 21477849 is about 4634.4200284394. The cubic root of 21477849 is about 277.9693607003.

The spelling of 21477849 in words is "twenty-one million, four hundred seventy-seven thousand, eight hundred forty-nine".