121291831 has 4 divisors (see below), whose sum is σ = 121743000. Its totient is φ = 120840664.

The previous prime is 121291799. The next prime is 121291847. The reversal of 121291831 is 138192121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121291831 - 2⁵ = 121291799 is a prime.

It is a super-2 number, since 2×121291831² = 29423416534665122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121291831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121261831) 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, 225181 + ... + 225718.

It is an arithmetic number, because the mean of its divisors is an integer number (30435750).

Almost surely, 2^121291831 is an apocalyptic number.

121291831 is a deficient number, since it is larger than the sum of its proper divisors (451169).

121291831 is an equidigital number, since it uses as much as digits as its factorization.

121291831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451168.

The product of its digits is 864, while the sum is 28.

The square root of 121291831 is about 11013.2570568384. The cubic root of 121291831 is about 495.0060618922.

The spelling of 121291831 in words is "one hundred twenty-one million, two hundred ninety-one thousand, eight hundred thirty-one".