121725157 has 4 divisors (see below), whose sum is σ = 122164876. Its totient is φ = 121285440.

The previous prime is 121725143. The next prime is 121725167. The reversal of 121725157 is 751527121.

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

It can be written as a sum of positive squares in 2 ways, for example, as 27363361 + 94361796 = 5231^2 + 9714^2 .

It is a cyclic number.

It is not a de Polignac number, because 121725157 - 2⁷ = 121725029 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 (121725137) 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, 219444 + ... + 219997.

It is an arithmetic number, because the mean of its divisors is an integer number (30541219).

Almost surely, 2^121725157 is an apocalyptic number.

It is an amenable number.

121725157 is a deficient number, since it is larger than the sum of its proper divisors (439719).

121725157 is an equidigital number, since it uses as much as digits as its factorization.

121725157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439718.

The product of its digits is 4900, while the sum is 31.

The square root of 121725157 is about 11032.9124441373. The cubic root of 121725157 is about 495.5948458793.

The spelling of 121725157 in words is "one hundred twenty-one million, seven hundred twenty-five thousand, one hundred fifty-seven".