121512009645 has 24 divisors (see below), whose sum is σ = 226822419096. Its totient is φ = 59821296768.

The previous prime is 121512009623. The next prime is 121512009649. The reversal of 121512009645 is 546900215121.

121512009645 is a `hidden beast` number, since 1 + 2 + 1 + 5 + 1 + 2 + 0 + 0 + 9 + 645 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2226046761 + 119285962884 = 47181^2 + 345378^2 .

It is not a de Polignac number, because 121512009645 - 2⁶ = 121512009581 is a prime.

It is a super-3 number, since 3×121512009645³ (a number of 34 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121512009649) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 103855834 + ... + 103857003.

It is an arithmetic number, because the mean of its divisors is an integer number (9450934129).

Almost surely, 2^121512009645 is an apocalyptic number.

121512009645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121512009645 is a deficient number, since it is larger than the sum of its proper divisors (105310409451).

121512009645 is a wasteful number, since it uses less digits than its factorization.

121512009645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207712861 (or 207712858 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The spelling of 121512009645 in words is "one hundred twenty-one billion, five hundred twelve million, nine thousand, six hundred forty-five".