42145521 has 8 divisors (see below), whose sum is σ = 61302624. Its totient is φ = 25542720.

The previous prime is 42145513. The next prime is 42145541. The reversal of 42145521 is 12554124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42145521 - 2³ = 42145513 is a prime.

It is a super-2 number, since 2×42145521² = 3552489880722882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42145491 and 42145500.

It is not an unprimeable number, because it can be changed into a prime (42145541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 638536 + ... + 638601.

It is an arithmetic number, because the mean of its divisors is an integer number (7662828).

Almost surely, 2^42145521 is an apocalyptic number.

It is an amenable number.

42145521 is a deficient number, since it is larger than the sum of its proper divisors (19157103).

42145521 is a wasteful number, since it uses less digits than its factorization.

42145521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277151.

The product of its digits is 1600, while the sum is 24.

The square root of 42145521 is about 6491.9581791629. The cubic root of 42145521 is about 348.0036579745.

Adding to 42145521 its reverse (12554124), we get a palindrome (54699645).

The spelling of 42145521 in words is "forty-two million, one hundred forty-five thousand, five hundred twenty-one".