21436145 has 16 divisors (see below), whose sum is σ = 26516160. Its totient is φ = 16626624.

The previous prime is 21436117. The next prime is 21436147. The reversal of 21436145 is 54163412.

It is a cyclic number.

It is not a de Polignac number, because 21436145 - 2⁸ = 21435889 is a prime.

It is a super-2 number, since 2×21436145² = 919016624922050, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (21436147) 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 15 ways as a sum of consecutive naturals, for example, 38207 + ... + 38763.

It is an arithmetic number, because the mean of its divisors is an integer number (1657260).

Almost surely, 2^21436145 is an apocalyptic number.

It is an amenable number.

21436145 is a deficient number, since it is larger than the sum of its proper divisors (5080015).

21436145 is a wasteful number, since it uses less digits than its factorization.

21436145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784.

The product of its digits is 2880, while the sum is 26.

The square root of 21436145 is about 4629.9184658048. The cubic root of 21436145 is about 277.7893311047.

Adding to 21436145 its reverse (54163412), we get a palindrome (75599557).

The spelling of 21436145 in words is "twenty-one million, four hundred thirty-six thousand, one hundred forty-five".