42513251 has 4 divisors (see below), whose sum is σ = 46378104. Its totient is φ = 38648400.

The previous prime is 42513227. The next prime is 42513281. The reversal of 42513251 is 15231524.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42513251 - 2¹⁸ = 42251107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42513221) 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, 1932410 + ... + 1932431.

It is an arithmetic number, because the mean of its divisors is an integer number (11594526).

Almost surely, 2^42513251 is an apocalyptic number.

42513251 is a deficient number, since it is larger than the sum of its proper divisors (3864853).

42513251 is a wasteful number, since it uses less digits than its factorization.

42513251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3864852.

The product of its digits is 1200, while the sum is 23.

The square root of 42513251 is about 6520.2186313037. The cubic root of 42513251 is about 349.0128675097.

Adding to 42513251 its reverse (15231524), we get a palindrome (57744775).

The spelling of 42513251 in words is "forty-two million, five hundred thirteen thousand, two hundred fifty-one".