4145023521 has 24 divisors (see below), whose sum is σ = 6351292584. Its totient is φ = 2595939840.

The previous prime is 4145023409. The next prime is 4145023529. The reversal of 4145023521 is 1253205414.

It can be written as a sum of positive squares in 4 ways, for example, as 1616040000 + 2528983521 = 40200^2 + 50289^2 .

It is not a de Polignac number, because 4145023521 - 2⁹ = 4145023009 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (4145023529) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57735 + ... + 107811.

It is an arithmetic number, because the mean of its divisors is an integer number (264637191).

Almost surely, 2^4145023521 is an apocalyptic number.

It is an amenable number.

4145023521 is a deficient number, since it is larger than the sum of its proper divisors (2206269063).

4145023521 is a wasteful number, since it uses less digits than its factorization.

4145023521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50641 (or 50638 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 4145023521 is about 64381.8570794599. The cubic root of 4145023521 is about 1606.3579726134.

Adding to 4145023521 its reverse (1253205414), we get a palindrome (5398228935).

The spelling of 4145023521 in words is "four billion, one hundred forty-five million, twenty-three thousand, five hundred twenty-one".