121142509 has 4 divisors (see below), whose sum is σ = 121381020. Its totient is φ = 120904000.

The previous prime is 121142503. The next prime is 121142519. The reversal of 121142509 is 905241121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 905241121 = 379 ⋅2388499.

It can be written as a sum of positive squares in 2 ways, for example, as 83356900 + 37785609 = 9130^2 + 6147^2 .

It is a cyclic number.

It is not a de Polignac number, because 121142509 - 2²⁵ = 87588077 is a prime.

It is a super-3 number, since 3×121142509³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121142503) 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 in 3 ways as a sum of consecutive naturals, for example, 118492 + ... + 119509.

It is an arithmetic number, because the mean of its divisors is an integer number (30345255).

Almost surely, 2^121142509 is an apocalyptic number.

It is an amenable number.

121142509 is a deficient number, since it is larger than the sum of its proper divisors (238511).

121142509 is an equidigital number, since it uses as much as digits as its factorization.

121142509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238510.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 121142509 is about 11006.4757756514. The cubic root of 121142509 is about 494.8028449962.

The spelling of 121142509 in words is "one hundred twenty-one million, one hundred forty-two thousand, five hundred nine".