64991311 has 8 divisors (see below), whose sum is σ = 81028224. Its totient is φ = 50642520.

The previous prime is 64991287. The next prime is 64991321. The reversal of 64991311 is 11319946.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64991311 - 2⁵ = 64991279 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 (64991321) 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 in 7 ways as a sum of consecutive naturals, for example, 421945 + ... + 422098.

It is an arithmetic number, because the mean of its divisors is an integer number (10128528).

Almost surely, 2^64991311 is an apocalyptic number.

64991311 is a deficient number, since it is larger than the sum of its proper divisors (16036913).

64991311 is a wasteful number, since it uses less digits than its factorization.

64991311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844061.

The product of its digits is 5832, while the sum is 34.

The square root of 64991311 is about 8061.7188613843. The cubic root of 64991311 is about 402.0546591189.

The spelling of 64991311 in words is "sixty-four million, nine hundred ninety-one thousand, three hundred eleven".