64236991 has 24 divisors (see below), whose sum is σ = 83094144. Its totient is φ = 49170240.

The previous prime is 64236983. The next prime is 64237003. The reversal of 64236991 is 19963246.

It is not a de Polignac number, because 64236991 - 2³ = 64236983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64231991) 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 23 ways as a sum of consecutive naturals, for example, 18121 + ... + 21373.

It is an arithmetic number, because the mean of its divisors is an integer number (3462256).

Almost surely, 2^64236991 is an apocalyptic number.

64236991 is a deficient number, since it is larger than the sum of its proper divisors (18857153).

64236991 is a wasteful number, since it uses less digits than its factorization.

64236991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3311 (or 3304 counting only the distinct ones).

The product of its digits is 69984, while the sum is 40.

The square root of 64236991 is about 8014.7982507359. The cubic root of 64236991 is about 400.4931230743.

The spelling of 64236991 in words is "sixty-four million, two hundred thirty-six thousand, nine hundred ninety-one".