75121138 has 4 divisors (see below), whose sum is σ = 112681710. Its totient is φ = 37560568.

The previous prime is 75121133. The next prime is 75121139. The reversal of 75121138 is 83112157.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83112157 = 661 ⋅125737.

It can be written as a sum of positive squares in only one way, i.e., 40157569 + 34963569 = 6337^2 + 5913^2 .

It is not an unprimeable number, because it can be changed into a prime (75121133) 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 as a sum of consecutive naturals, namely, 18780283 + ... + 18780286.

Almost surely, 2^75121138 is an apocalyptic number.

75121138 is a deficient number, since it is larger than the sum of its proper divisors (37560572).

75121138 is a wasteful number, since it uses less digits than its factorization.

75121138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37560571.

The product of its digits is 1680, while the sum is 28.

The square root of 75121138 is about 8667.2451217212. The cubic root of 75121138 is about 421.9432588446.

The spelling of 75121138 in words is "seventy-five million, one hundred twenty-one thousand, one hundred thirty-eight".