42787819 has 2 divisors, whose sum is σ = 42787820. Its totient is φ = 42787818.

The previous prime is 42787817. The next prime is 42787831. The reversal of 42787819 is 91878724.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42787819 - 2¹ = 42787817 is a prime.

It is a super-2 number, since 2×42787819² = 3661594909553522, which contains 22 as substring.

Together with 42787817, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42787817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21393909 + 21393910.

It is an arithmetic number, because the mean of its divisors is an integer number (21393910).

Almost surely, 2^42787819 is an apocalyptic number.

42787819 is a deficient number, since it is larger than the sum of its proper divisors (1).

42787819 is an equidigital number, since it uses as much as digits as its factorization.

42787819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 225792, while the sum is 46.

The square root of 42787819 is about 6541.2398671811. The cubic root of 42787819 is about 349.7626118165.

The spelling of 42787819 in words is "forty-two million, seven hundred eighty-seven thousand, eight hundred nineteen".