75639989 has 2 divisors, whose sum is σ = 75639990. Its totient is φ = 75639988.

The previous prime is 75639973. The next prime is 75639997. The reversal of 75639989 is 98993657.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66699889 + 8940100 = 8167^2 + 2990^2 .

It is a cyclic number.

It is not a de Polignac number, because 75639989 - 2⁴ = 75639973 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75639959) 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 as a sum of consecutive naturals, namely, 37819994 + 37819995.

It is an arithmetic number, because the mean of its divisors is an integer number (37819995).

Almost surely, 2^75639989 is an apocalyptic number.

It is an amenable number.

75639989 is a deficient number, since it is larger than the sum of its proper divisors (1).

75639989 is an equidigital number, since it uses as much as digits as its factorization.

75639989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3674160, while the sum is 56.

The square root of 75639989 is about 8697.1253296707. The cubic root of 75639989 is about 422.9124648642.

The spelling of 75639989 in words is "seventy-five million, six hundred thirty-nine thousand, nine hundred eighty-nine".