21142369 has 8 divisors (see below), whose sum is σ = 21713120. Its totient is φ = 20575296.

The previous prime is 21142361. The next prime is 21142379. The reversal of 21142369 is 96324112.

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 21142369 - 2³ = 21142361 is a prime.

It is a super-2 number, since 2×21142369² = 893999533864322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21142361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13762 + ... + 15220.

It is an arithmetic number, because the mean of its divisors is an integer number (2714140).

Almost surely, 2^21142369 is an apocalyptic number.

It is an amenable number.

21142369 is a deficient number, since it is larger than the sum of its proper divisors (570751).

21142369 is a wasteful number, since it uses less digits than its factorization.

21142369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1839.

The product of its digits is 2592, while the sum is 28.

The square root of 21142369 is about 4598.0831875902. The cubic root of 21142369 is about 276.5144826826.

The spelling of 21142369 in words is "twenty-one million, one hundred forty-two thousand, three hundred sixty-nine".