121549157 has 4 divisors (see below), whose sum is σ = 122752716. Its totient is φ = 120345600.

The previous prime is 121549151. The next prime is 121549159. The reversal of 121549157 is 751945121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 751945121 = 19 ⋅39576059.

It can be written as a sum of positive squares in 2 ways, for example, as 74200996 + 47348161 = 8614^2 + 6881^2 .

It is a cyclic number.

It is not a de Polignac number, because 121549157 - 2⁸ = 121548901 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 (121549151) 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, 601628 + ... + 601829.

It is an arithmetic number, because the mean of its divisors is an integer number (30688179).

Almost surely, 2^121549157 is an apocalyptic number.

It is an amenable number.

121549157 is a deficient number, since it is larger than the sum of its proper divisors (1203559).

121549157 is a wasteful number, since it uses less digits than its factorization.

121549157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1203558.

The product of its digits is 12600, while the sum is 35.

The square root of 121549157 is about 11024.9334238353. The cubic root of 121549157 is about 495.3558737346.

The spelling of 121549157 in words is "one hundred twenty-one million, five hundred forty-nine thousand, one hundred fifty-seven".