121265609 has 4 divisors (see below), whose sum is σ = 121360404. Its totient is φ = 121170816.

The previous prime is 121265597. The next prime is 121265623. The reversal of 121265609 is 906562121.

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: 906562121 = 1051 ⋅862571.

It can be written as a sum of positive squares in 2 ways, for example, as 114490000 + 6775609 = 10700^2 + 2603^2 .

It is a cyclic number.

It is not a de Polignac number, because 121265609 - 2¹² = 121261513 is a prime.

It is a super-2 number, since 2×121265609² = 29410695852281762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121265699) 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, 45452 + ... + 48045.

It is an arithmetic number, because the mean of its divisors is an integer number (30340101).

Almost surely, 2^121265609 is an apocalyptic number.

It is an amenable number.

121265609 is a deficient number, since it is larger than the sum of its proper divisors (94795).

121265609 is an equidigital number, since it uses as much as digits as its factorization.

121265609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94794.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 121265609 is about 11012.0665181427. The cubic root of 121265609 is about 494.9703876446.

It can be divided in two parts, 12 and 1265609, that added together give a palindrome (1265621).

The spelling of 121265609 in words is "one hundred twenty-one million, two hundred sixty-five thousand, six hundred nine".