64128791 has 2 divisors, whose sum is σ = 64128792. Its totient is φ = 64128790.

The previous prime is 64128787. The next prime is 64128809. The reversal of 64128791 is 19782146.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64128791 - 2² = 64128787 is a prime.

It is a super-2 number, since 2×64128791² = 8225003670243362, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64128731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32064395 + 32064396.

It is an arithmetic number, because the mean of its divisors is an integer number (32064396).

Almost surely, 2^64128791 is an apocalyptic number.

64128791 is a deficient number, since it is larger than the sum of its proper divisors (1).

64128791 is an equidigital number, since it uses as much as digits as its factorization.

64128791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 64128791 is about 8008.0453919792. The cubic root of 64128791 is about 400.2681348025.

The spelling of 64128791 in words is "sixty-four million, one hundred twenty-eight thousand, seven hundred ninety-one".