64693191 has 4 divisors (see below), whose sum is σ = 86257592. Its totient is φ = 43128792.

The previous prime is 64693169. The next prime is 64693193. The reversal of 64693191 is 19139646.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 64693191 - 2⁵ = 64693159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64693193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10782196 + ... + 10782201.

It is an arithmetic number, because the mean of its divisors is an integer number (21564398).

Almost surely, 2^64693191 is an apocalyptic number.

64693191 is a deficient number, since it is larger than the sum of its proper divisors (21564401).

64693191 is a wasteful number, since it uses less digits than its factorization.

64693191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21564400.

The product of its digits is 34992, while the sum is 39.

The square root of 64693191 is about 8043.2077556159. The cubic root of 64693191 is about 401.4389651575.

The spelling of 64693191 in words is "sixty-four million, six hundred ninety-three thousand, one hundred ninety-one".