121649819 has 2 divisors, whose sum is σ = 121649820. Its totient is φ = 121649818.

The previous prime is 121649743. The next prime is 121649831. The reversal of 121649819 is 918946121.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121649819 is a prime.

It is a super-2 number, since 2×121649819² = 29597356925465522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121649839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60824909 + 60824910.

It is an arithmetic number, because the mean of its divisors is an integer number (60824910).

Almost surely, 2^121649819 is an apocalyptic number.

121649819 is a deficient number, since it is larger than the sum of its proper divisors (1).

121649819 is an equidigital number, since it uses as much as digits as its factorization.

121649819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 41.

The square root of 121649819 is about 11029.4976766850. The cubic root of 121649819 is about 495.4925804398.

The spelling of 121649819 in words is "one hundred twenty-one million, six hundred forty-nine thousand, eight hundred nineteen".