42507251 has 2 divisors, whose sum is σ = 42507252. Its totient is φ = 42507250.

The previous prime is 42507247. The next prime is 42507271. The reversal of 42507251 is 15270524.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42507251 - 2² = 42507247 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42507251.

It is not a weakly prime, because it can be changed into another prime (42507211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21253625 + 21253626.

It is an arithmetic number, because the mean of its divisors is an integer number (21253626).

Almost surely, 2^42507251 is an apocalyptic number.

42507251 is a deficient number, since it is larger than the sum of its proper divisors (1).

42507251 is an equidigital number, since it uses as much as digits as its factorization.

42507251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 42507251 is about 6519.7585077977. The cubic root of 42507251 is about 348.9964477215.

Adding to 42507251 its reverse (15270524), we get a palindrome (57777775).

The spelling of 42507251 in words is "forty-two million, five hundred seven thousand, two hundred fifty-one".