1961125099 has 2 divisors, whose sum is σ = 1961125100. Its totient is φ = 1961125098.

The previous prime is 1961125091. The next prime is 1961125121. The reversal of 1961125099 is 9905211691.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1961125099 - 2³ = 1961125091 is a prime.

It is not a weakly prime, because it can be changed into another prime (1961125091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 980562549 + 980562550.

It is an arithmetic number, because the mean of its divisors is an integer number (980562550).

Almost surely, 2^1961125099 is an apocalyptic number.

1961125099 is a deficient number, since it is larger than the sum of its proper divisors (1).

1961125099 is an equidigital number, since it uses as much as digits as its factorization.

1961125099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43740, while the sum is 43.

The square root of 1961125099 is about 44284.5921173493. The cubic root of 1961125099 is about 1251.7043628483.

The spelling of 1961125099 in words is "one billion, nine hundred sixty-one million, one hundred twenty-five thousand, ninety-nine".