42520251 has 16 divisors (see below), whose sum is σ = 58798080. Its totient is φ = 27303360.

The previous prime is 42520217. The next prime is 42520259. The reversal of 42520251 is 15202524.

It is a happy number.

It is not a de Polignac number, because 42520251 - 2⁶ = 42520187 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42520259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21271 + ... + 23183.

It is an arithmetic number, because the mean of its divisors is an integer number (3674880).

Almost surely, 2^42520251 is an apocalyptic number.

42520251 is a deficient number, since it is larger than the sum of its proper divisors (16277829).

42520251 is a wasteful number, since it uses less digits than its factorization.

42520251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2186.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 42520251 is about 6520.7554010253. The cubic root of 42520251 is about 349.0320219767.

Adding to 42520251 its reverse (15202524), we get a palindrome (57722775).

The spelling of 42520251 in words is "forty-two million, five hundred twenty thousand, two hundred fifty-one".