64061815 has 4 divisors (see below), whose sum is σ = 76874184. Its totient is φ = 51249448.

The previous prime is 64061791. The next prime is 64061819. The reversal of 64061815 is 51816046.

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

It is a cyclic number.

It is not a de Polignac number, because 64061815 - 2⁹ = 64061303 is a prime.

It is a super-2 number, since 2×64061815² = 8207832282188450, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64061819) 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, 6406177 + ... + 6406186.

It is an arithmetic number, because the mean of its divisors is an integer number (19218546).

Almost surely, 2^64061815 is an apocalyptic number.

64061815 is a deficient number, since it is larger than the sum of its proper divisors (12812369).

64061815 is a wasteful number, since it uses less digits than its factorization.

64061815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12812368.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 64061815 is about 8003.8625050659. The cubic root of 64061815 is about 400.1287398107.

The spelling of 64061815 in words is "sixty-four million, sixty-one thousand, eight hundred fifteen".