65541425021 has 4 divisors (see below), whose sum is σ = 65541959100. Its totient is φ = 65540890944.

The previous prime is 65541425017. The next prime is 65541425057. The reversal of 65541425021 is 12052414556.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 31121899396 + 34419525625 = 176414^2 + 185525^2 .

It is a cyclic number.

It is not a de Polignac number, because 65541425021 - 2² = 65541425017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65541425011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19595 + ... + 362583.

It is an arithmetic number, because the mean of its divisors is an integer number (16385489775).

Almost surely, 2^65541425021 is an apocalyptic number.

It is an amenable number.

65541425021 is a deficient number, since it is larger than the sum of its proper divisors (534079).

65541425021 is a wasteful number, since it uses less digits than its factorization.

65541425021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534078.

The product of its (nonzero) digits is 48000, while the sum is 35.

Adding to 65541425021 its reverse (12052414556), we get a palindrome (77593839577).

The spelling of 65541425021 in words is "sixty-five billion, five hundred forty-one million, four hundred twenty-five thousand, twenty-one".