661075099 has 2 divisors, whose sum is σ = 661075100. Its totient is φ = 661075098.

The previous prime is 661075091. The next prime is 661075111. The reversal of 661075099 is 990570166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661075099 - 2³ = 661075091 is a prime.

It is not a weakly prime, because it can be changed into another prime (661075091) 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, 330537549 + 330537550.

It is an arithmetic number, because the mean of its divisors is an integer number (330537550).

Almost surely, 2^661075099 is an apocalyptic number.

661075099 is a deficient number, since it is larger than the sum of its proper divisors (1).

661075099 is an equidigital number, since it uses as much as digits as its factorization.

661075099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 102060, while the sum is 43.

The square root of 661075099 is about 25711.3807291635. The cubic root of 661075099 is about 871.1312623390.

The spelling of 661075099 in words is "six hundred sixty-one million, seventy-five thousand, ninety-nine".