21713635 has 8 divisors (see below), whose sum is σ = 26760816. Its totient is φ = 16901280.

The previous prime is 21713611. The next prime is 21713639. The reversal of 21713635 is 53631712.

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

It is not a de Polignac number, because 21713635 - 2⁵ = 21713603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21713639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58501 + ... + 58870.

It is an arithmetic number, because the mean of its divisors is an integer number (3345102).

Almost surely, 2^21713635 is an apocalyptic number.

21713635 is a deficient number, since it is larger than the sum of its proper divisors (5047181).

21713635 is a wasteful number, since it uses less digits than its factorization.

21713635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117413.

The product of its digits is 3780, while the sum is 28.

The square root of 21713635 is about 4659.7891583204. The cubic root of 21713635 is about 278.9828528835.

The spelling of 21713635 in words is "twenty-one million, seven hundred thirteen thousand, six hundred thirty-five".