42097819 has 2 divisors, whose sum is σ = 42097820. Its totient is φ = 42097818.

The previous prime is 42097813. The next prime is 42097829. The reversal of 42097819 is 91879024.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42097819 - 2⁷ = 42097691 is a prime.

It is a super-2 number, since 2×42097819² = 3544452729113522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (42097813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21048909 + 21048910.

It is an arithmetic number, because the mean of its divisors is an integer number (21048910).

Almost surely, 2^42097819 is an apocalyptic number.

42097819 is a deficient number, since it is larger than the sum of its proper divisors (1).

42097819 is an equidigital number, since it uses as much as digits as its factorization.

42097819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 42097819 is about 6488.2832089853. The cubic root of 42097819 is about 347.8723135511.

It can be divided in two parts, 42097 and 819, that multiplied together give a palindrome (34477443).

The spelling of 42097819 in words is "forty-two million, ninety-seven thousand, eight hundred nineteen".