64043987 has 4 divisors (see below), whose sum is σ = 73193136. Its totient is φ = 54894840.

The previous prime is 64043951. The next prime is 64043989. The reversal of 64043987 is 78934046.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78934046 = 2 ⋅39467023.

It is not a de Polignac number, because 64043987 - 2¹⁴ = 64027603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64043989) 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, 4574564 + ... + 4574577.

It is an arithmetic number, because the mean of its divisors is an integer number (18298284).

Almost surely, 2^64043987 is an apocalyptic number.

64043987 is a deficient number, since it is larger than the sum of its proper divisors (9149149).

64043987 is an equidigital number, since it uses as much as digits as its factorization.

64043987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9149148.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 64043987 is about 8002.7487152853. The cubic root of 64043987 is about 400.0916185968.

The spelling of 64043987 in words is "sixty-four million, forty-three thousand, nine hundred eighty-seven".