65369981 has 4 divisors (see below), whose sum is σ = 69215292. Its totient is φ = 61524672.

The previous prime is 65369971. The next prime is 65369987. The reversal of 65369981 is 18996356.

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

It can be written as a sum of positive squares in 2 ways, for example, as 46308025 + 19061956 = 6805^2 + 4366^2 .

It is a cyclic number.

It is not a de Polignac number, because 65369981 - 2²² = 61175677 is a prime.

It is a super-2 number, since 2×65369981² = 8546468831880722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65369987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1922630 + ... + 1922663.

It is an arithmetic number, because the mean of its divisors is an integer number (17303823).

Almost surely, 2^65369981 is an apocalyptic number.

It is an amenable number.

65369981 is a deficient number, since it is larger than the sum of its proper divisors (3845311).

65369981 is a wasteful number, since it uses less digits than its factorization.

65369981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3845310.

The product of its digits is 349920, while the sum is 47.

The square root of 65369981 is about 8085.1704372883. The cubic root of 65369981 is about 402.8340007628.

The spelling of 65369981 in words is "sixty-five million, three hundred sixty-nine thousand, nine hundred eighty-one".