64191857 has 2 divisors, whose sum is σ = 64191858. Its totient is φ = 64191856.

The previous prime is 64191833. The next prime is 64191901. The reversal of 64191857 is 75819146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62742241 + 1449616 = 7921^2 + 1204^2 .

It is a cyclic number.

It is not a de Polignac number, because 64191857 - 2¹⁴ = 64175473 is a prime.

It is equal to p_3795728 and since 64191857 and 3795728 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (64194857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32095928 + 32095929.

It is an arithmetic number, because the mean of its divisors is an integer number (32095929).

Almost surely, 2^64191857 is an apocalyptic number.

It is an amenable number.

64191857 is a deficient number, since it is larger than the sum of its proper divisors (1).

64191857 is an equidigital number, since it uses as much as digits as its factorization.

64191857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60480, while the sum is 41.

The square root of 64191857 is about 8011.9820893459. The cubic root of 64191857 is about 400.3993033428.

The spelling of 64191857 in words is "sixty-four million, one hundred ninety-one thousand, eight hundred fifty-seven".