65436021 has 18 divisors (see below), whose sum is σ = 109951062. Its totient is φ = 37391760.

The previous prime is 65436013. The next prime is 65436031. The reversal of 65436021 is 12063456.

65436021 is a `hidden beast` number, since 6 + 54 + 3 + 602 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 42107121 + 23328900 = 6489^2 + 4830^2 .

It is not a de Polignac number, because 65436021 - 2³ = 65436013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65436011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 73750 + ... + 74631.

Almost surely, 2^65436021 is an apocalyptic number.

It is an amenable number.

65436021 is a deficient number, since it is larger than the sum of its proper divisors (44515041).

65436021 is a wasteful number, since it uses less digits than its factorization.

65436021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148401 (or 148391 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 65436021 is about 8089.2534266148. The cubic root of 65436021 is about 402.9696094088.

Adding to 65436021 its reverse (12063456), we get a palindrome (77499477).

The spelling of 65436021 in words is "sixty-five million, four hundred thirty-six thousand, twenty-one".