21145365 has 48 divisors (see below), whose sum is σ = 39289536. Its totient is φ = 10483200.

The previous prime is 21145363. The next prime is 21145367. The reversal of 21145365 is 56354112.

It is an interprime number because it is at equal distance from previous prime (21145363) and next prime (21145367).

It is not a de Polignac number, because 21145365 - 2¹ = 21145363 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21145363) 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 47 ways as a sum of consecutive naturals, for example, 100110 + ... + 100320.

It is an arithmetic number, because the mean of its divisors is an integer number (818532).

Almost surely, 2^21145365 is an apocalyptic number.

It is an amenable number.

21145365 is a deficient number, since it is larger than the sum of its proper divisors (18144171).

21145365 is a wasteful number, since it uses less digits than its factorization.

21145365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370 (or 367 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 21145365 is about 4598.4089639787. The cubic root of 21145365 is about 276.5275433171.

Adding to 21145365 its reverse (56354112), we get a palindrome (77499477).

The spelling of 21145365 in words is "twenty-one million, one hundred forty-five thousand, three hundred sixty-five".