75121987 has 2 divisors, whose sum is σ = 75121988. Its totient is φ = 75121986.

The previous prime is 75121967. The next prime is 75121993. The reversal of 75121987 is 78912157.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 75121987 - 2¹⁵ = 75089219 is a prime.

It is not a weakly prime, because it can be changed into another prime (75121967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37560993 + 37560994.

It is an arithmetic number, because the mean of its divisors is an integer number (37560994).

Almost surely, 2^75121987 is an apocalyptic number.

75121987 is a deficient number, since it is larger than the sum of its proper divisors (1).

75121987 is an equidigital number, since it uses as much as digits as its factorization.

75121987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35280, while the sum is 40.

The square root of 75121987 is about 8667.2940990831. The cubic root of 75121987 is about 421.9448484037.

The spelling of 75121987 in words is "seventy-five million, one hundred twenty-one thousand, nine hundred eighty-seven".