64611993 has 16 divisors (see below), whose sum is σ = 87869376. Its totient is φ = 42219840.

The previous prime is 64611979. The next prime is 64612001. The reversal of 64611993 is 39911646.

It is not a de Polignac number, because 64611993 - 2⁸ = 64611737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64611923) 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, 80671 + ... + 81467.

It is an arithmetic number, because the mean of its divisors is an integer number (5491836).

Almost surely, 2^64611993 is an apocalyptic number.

It is an amenable number.

64611993 is a deficient number, since it is larger than the sum of its proper divisors (23257383).

64611993 is a wasteful number, since it uses less digits than its factorization.

64611993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1304.

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

The square root of 64611993 is about 8038.1585577793. The cubic root of 64611993 is about 401.2709429001.

The spelling of 64611993 in words is "sixty-four million, six hundred eleven thousand, nine hundred ninety-three".