121780605 has 16 divisors (see below), whose sum is σ = 206311104. Its totient is φ = 61128960.

The previous prime is 121780573. The next prime is 121780609. The reversal of 121780605 is 506087121.

It is not a de Polignac number, because 121780605 - 2⁵ = 121780573 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121780609) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238531 + ... + 239040.

It is an arithmetic number, because the mean of its divisors is an integer number (12894444).

Almost surely, 2^121780605 is an apocalyptic number.

121780605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121780605 is a deficient number, since it is larger than the sum of its proper divisors (84530499).

121780605 is a wasteful number, since it uses less digits than its factorization.

121780605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477596.

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 121780605 is about 11035.4250031433. The cubic root of 121780605 is about 495.6700852471.

The spelling of 121780605 in words is "one hundred twenty-one million, seven hundred eighty thousand, six hundred five".