121645431 has 12 divisors (see below), whose sum is σ = 175810752. Its totient is φ = 81050496.

The previous prime is 121645399. The next prime is 121645439. The reversal of 121645431 is 134546121.

It is a happy number.

121645431 is a `hidden beast` number, since 12 + 1 + 645 + 4 + 3 + 1 = 666.

It is not a de Polignac number, because 121645431 - 2⁵ = 121645399 is a prime.

It is a super-2 number, since 2×121645431² = 29595221766351522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121645395 and 121645404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121645439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21370 + ... + 26456.

It is an arithmetic number, because the mean of its divisors is an integer number (14650896).

Almost surely, 2^121645431 is an apocalyptic number.

121645431 is a deficient number, since it is larger than the sum of its proper divisors (54165321).

121645431 is a wasteful number, since it uses less digits than its factorization.

121645431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7750 (or 7747 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 121645431 is about 11029.2987537740. The cubic root of 121645431 is about 495.4866227721.

The spelling of 121645431 in words is "one hundred twenty-one million, six hundred forty-five thousand, four hundred thirty-one".