121666545 has 192 divisors, whose sum is σ = 294787584. Its totient is φ = 44789760.

The previous prime is 121666541. The next prime is 121666547. The reversal of 121666545 is 545666121.

It is not a de Polignac number, because 121666545 - 2² = 121666541 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (121666541) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1666629 + ... + 1666701.

It is an arithmetic number, because the mean of its divisors is an integer number (1535352).

Almost surely, 2^121666545 is an apocalyptic number.

121666545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121666545 is an abundant number, since it is smaller than the sum of its proper divisors (173121039).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121666545 is a wasteful number, since it uses less digits than its factorization.

121666545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 149 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 121666545 is about 11030.2558900508. The cubic root of 121666545 is about 495.5152883215.

It can be divided in two parts, 121 and 666545, that added together give a palindrome (666666).

The spelling of 121666545 in words is "one hundred twenty-one million, six hundred sixty-six thousand, five hundred forty-five".