123842819 has 2 divisors, whose sum is σ = 123842820. Its totient is φ = 123842818.

The previous prime is 123842813. The next prime is 123842843. The reversal of 123842819 is 918248321.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123842819 is a prime.

It is a super-2 number, since 2×123842819² = 30674087635733522, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (123842813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61921409 + 61921410.

It is an arithmetic number, because the mean of its divisors is an integer number (61921410).

Almost surely, 2^123842819 is an apocalyptic number.

123842819 is a deficient number, since it is larger than the sum of its proper divisors (1).

123842819 is an equidigital number, since it uses as much as digits as its factorization.

123842819 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27648, while the sum is 38.

The square root of 123842819 is about 11128.4688524523. The cubic root of 123842819 is about 498.4523062310.

The spelling of 123842819 in words is "one hundred twenty-three million, eight hundred forty-two thousand, eight hundred nineteen".