64998391 has 16 divisors (see below), whose sum is σ = 69439680. Its totient is φ = 60712960.

The previous prime is 64998389. The next prime is 64998421. The reversal of 64998391 is 19389946.

It is a cyclic number.

It is not a de Polignac number, because 64998391 - 2¹ = 64998389 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 (64998331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 231171 + ... + 231451.

It is an arithmetic number, because the mean of its divisors is an integer number (4339980).

Almost surely, 2^64998391 is an apocalyptic number.

64998391 is a deficient number, since it is larger than the sum of its proper divisors (4441289).

64998391 is a wasteful number, since it uses less digits than its factorization.

64998391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506.

The product of its digits is 419904, while the sum is 49.

The square root of 64998391 is about 8062.1579617370. The cubic root of 64998391 is about 402.0692582173.

The spelling of 64998391 in words is "sixty-four million, nine hundred ninety-eight thousand, three hundred ninety-one".