121657429 has 4 divisors (see below), whose sum is σ = 122862060. Its totient is φ = 120452800.

The previous prime is 121657381. The next prime is 121657463. The reversal of 121657429 is 924756121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 924756121 = 2297 ⋅402593.

It can be written as a sum of positive squares in 2 ways, for example, as 85932900 + 35724529 = 9270^2 + 5977^2 .

It is a cyclic number.

It is not a de Polignac number, because 121657429 - 2⁷ = 121657301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121657229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 602164 + ... + 602365.

It is an arithmetic number, because the mean of its divisors is an integer number (30715515).

Almost surely, 2^121657429 is an apocalyptic number.

It is an amenable number.

121657429 is a deficient number, since it is larger than the sum of its proper divisors (1204631).

121657429 is a wasteful number, since it uses less digits than its factorization.

121657429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1204630.

The product of its digits is 30240, while the sum is 37.

The square root of 121657429 is about 11029.8426552694. The cubic root of 121657429 is about 495.5029123360.

The spelling of 121657429 in words is "one hundred twenty-one million, six hundred fifty-seven thousand, four hundred twenty-nine".