65209987 has 4 divisors (see below), whose sum is σ = 65286936. Its totient is φ = 65133040.

The previous prime is 65209939. The next prime is 65210039. The reversal of 65209987 is 78990256.

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 65209987 - 2²³ = 56821379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65209087) 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, 37189 + ... + 38902.

It is an arithmetic number, because the mean of its divisors is an integer number (16321734).

Almost surely, 2^65209987 is an apocalyptic number.

65209987 is a deficient number, since it is larger than the sum of its proper divisors (76949).

65209987 is an equidigital number, since it uses as much as digits as its factorization.

65209987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76948.

The product of its (nonzero) digits is 272160, while the sum is 46.

The square root of 65209987 is about 8075.2700883624. The cubic root of 65209987 is about 402.5050848733.

The spelling of 65209987 in words is "sixty-five million, two hundred nine thousand, nine hundred eighty-seven".