64001891 has 2 divisors, whose sum is σ = 64001892.
Its totient is φ = 64001890.
The previous prime is 64001867. The next prime is 64001909. The reversal of 64001891 is 19810046.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 64001891 - 218 = 63739747 is a prime.
It is a Chen prime.
It is not a weakly prime, because it can be changed into another prime (64001851) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32000945 + 32000946.
It is an arithmetic number, because the mean of its divisors is an integer number (32000946).
Almost surely, 264001891 is an apocalyptic number.
64001891 is a deficient number, since it is larger than the sum of its proper divisors (1).
64001891 is an equidigital number, since it uses as much as digits as its factorization.
64001891 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 1728, while the sum is 29.
The square root of 64001891 is about 8000.1181866270.
The cubic root of 64001891 is about 400.0039395445.
The spelling of 64001891 in words is "sixty-four million, one thousand, eight hundred ninety-one".