121431251 has 4 divisors (see below), whose sum is σ = 122176392. Its totient is φ = 120686112.

The previous prime is 121431239. The next prime is 121431257. The reversal of 121431251 is 152134121.

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 121431251 - 2¹⁸ = 121169107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121431257) 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, 372326 + ... + 372651.

It is an arithmetic number, because the mean of its divisors is an integer number (30544098).

Almost surely, 2^121431251 is an apocalyptic number.

121431251 is a deficient number, since it is larger than the sum of its proper divisors (745141).

121431251 is an equidigital number, since it uses as much as digits as its factorization.

121431251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 745140.

The product of its digits is 240, while the sum is 20.

The square root of 121431251 is about 11019.5848832885. The cubic root of 121431251 is about 495.1956523442.

Adding to 121431251 its reverse (152134121), we get a palindrome (273565372).

The spelling of 121431251 in words is "one hundred twenty-one million, four hundred thirty-one thousand, two hundred fifty-one".