1951984109 has 2 divisors, whose sum is σ = 1951984110. Its totient is φ = 1951984108.

The previous prime is 1951984063. The next prime is 1951984121. The reversal of 1951984109 is 9014891591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1785316009 + 166668100 = 42253^2 + 12910^2 .

It is a cyclic number.

It is not a de Polignac number, because 1951984109 - 2⁸ = 1951983853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1951984609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 975992054 + 975992055.

It is an arithmetic number, because the mean of its divisors is an integer number (975992055).

Almost surely, 2^1951984109 is an apocalyptic number.

It is an amenable number.

1951984109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1951984109 is an equidigital number, since it uses as much as digits as its factorization.

1951984109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 116640, while the sum is 47.

The square root of 1951984109 is about 44181.2642304405. The cubic root of 1951984109 is about 1249.7565625136.

The spelling of 1951984109 in words is "one billion, nine hundred fifty-one million, nine hundred eighty-four thousand, one hundred nine".