75886721 has 2 divisors, whose sum is σ = 75886722. Its totient is φ = 75886720.

The previous prime is 75886673. The next prime is 75886739. The reversal of 75886721 is 12768857.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74632321 + 1254400 = 8639^2 + 1120^2 .

It is an emirp because it is prime and its reverse (12768857) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-75886721 is a prime.

It is not a weakly prime, because it can be changed into another prime (75886751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37943360 + 37943361.

It is an arithmetic number, because the mean of its divisors is an integer number (37943361).

Almost surely, 2^75886721 is an apocalyptic number.

It is an amenable number.

75886721 is a deficient number, since it is larger than the sum of its proper divisors (1).

75886721 is an equidigital number, since it uses as much as digits as its factorization.

75886721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 188160, while the sum is 44.

The square root of 75886721 is about 8711.2984680816. The cubic root of 75886721 is about 423.3718020856.

The spelling of 75886721 in words is "seventy-five million, eight hundred eighty-six thousand, seven hundred twenty-one".