42503521 has 4 divisors (see below), whose sum is σ = 42681600. Its totient is φ = 42325444.

The previous prime is 42503497. The next prime is 42503533. The reversal of 42503521 is 12530524.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42503521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42503492 and 42503501.

It is not an unprimeable number, because it can be changed into a prime (42503561) 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, 88681 + ... + 89158.

It is an arithmetic number, because the mean of its divisors is an integer number (10670400).

Almost surely, 2^42503521 is an apocalyptic number.

It is an amenable number.

42503521 is a deficient number, since it is larger than the sum of its proper divisors (178079).

42503521 is a wasteful number, since it uses less digits than its factorization.

42503521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178078.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 42503521 is about 6519.4724479823. The cubic root of 42503521 is about 348.9862393077.

The spelling of 42503521 in words is "forty-two million, five hundred three thousand, five hundred twenty-one".