42002431 has 2 divisors, whose sum is σ = 42002432. Its totient is φ = 42002430.

The previous prime is 42002383. The next prime is 42002449. The reversal of 42002431 is 13420024.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42002431 - 2¹¹ = 42000383 is a prime.

It is a super-2 number, since 2×42002431² = 3528408419819522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42002231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21001215 + 21001216.

It is an arithmetic number, because the mean of its divisors is an integer number (21001216).

Almost surely, 2^42002431 is an apocalyptic number.

42002431 is a deficient number, since it is larger than the sum of its proper divisors (1).

42002431 is an equidigital number, since it uses as much as digits as its factorization.

42002431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 42002431 is about 6480.9282514158. The cubic root of 42002431 is about 347.6093708837.

Adding to 42002431 its reverse (13420024), we get a palindrome (55422455).

The spelling of 42002431 in words is "forty-two million, two thousand, four hundred thirty-one".