121540009 has 4 divisors (see below), whose sum is σ = 122116240. Its totient is φ = 120963780.

The previous prime is 121540007. The next prime is 121540033. The reversal of 121540009 is 900045121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 900045121 = 24317 ⋅37013.

It is a cyclic number.

It is not a de Polignac number, because 121540009 - 2¹ = 121540007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121540007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 287799 + ... + 288220.

It is an arithmetic number, because the mean of its divisors is an integer number (30529060).

Almost surely, 2^121540009 is an apocalyptic number.

It is an amenable number.

121540009 is a deficient number, since it is larger than the sum of its proper divisors (576231).

121540009 is an equidigital number, since it uses as much as digits as its factorization.

121540009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576230.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 121540009 is about 11024.5185382401. The cubic root of 121540009 is about 495.3434463092.

The spelling of 121540009 in words is "one hundred twenty-one million, five hundred forty thousand, nine".