75721691 has 2 divisors, whose sum is σ = 75721692. Its totient is φ = 75721690.

The previous prime is 75721673. The next prime is 75721733. The reversal of 75721691 is 19612757.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 75721691 - 2⁶ = 75721627 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (75721661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37860845 + 37860846.

It is an arithmetic number, because the mean of its divisors is an integer number (37860846).

Almost surely, 2^75721691 is an apocalyptic number.

75721691 is a deficient number, since it is larger than the sum of its proper divisors (1).

75721691 is an equidigital number, since it uses as much as digits as its factorization.

75721691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26460, while the sum is 38.

The square root of 75721691 is about 8701.8211312345. The cubic root of 75721691 is about 423.0646787107.

The spelling of 75721691 in words is "seventy-five million, seven hundred twenty-one thousand, six hundred ninety-one".