121209231 has 32 divisors (see below), whose sum is σ = 192745728. Its totient is φ = 66781440.

The previous prime is 121209229. The next prime is 121209239. The reversal of 121209231 is 132902121.

It is not a de Polignac number, because 121209231 - 2¹ = 121209229 is a prime.

It is a super-2 number, since 2×121209231² = 29383355359222722, which contains 22 as substring.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 121209198 and 121209207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121209239) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26635 + ... + 30851.

It is an arithmetic number, because the mean of its divisors is an integer number (6023304).

Almost surely, 2^121209231 is an apocalyptic number.

121209231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121209231 is a deficient number, since it is larger than the sum of its proper divisors (71536497).

121209231 is a wasteful number, since it uses less digits than its factorization.

121209231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4311.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 121209231 is about 11009.5063922049. The cubic root of 121209231 is about 494.8936696413.

The spelling of 121209231 in words is "one hundred twenty-one million, two hundred nine thousand, two hundred thirty-one".