84216709 has 4 divisors (see below), whose sum is σ = 84236940. Its totient is φ = 84196480.

The previous prime is 84216701. The next prime is 84216749. The reversal of 84216709 is 90761248.

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 44488900 + 39727809 = 6670^2 + 6303^2 .

It is a cyclic number.

It is not a de Polignac number, because 84216709 - 2³ = 84216701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84216701) 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, 1324 + ... + 13045.

It is an arithmetic number, because the mean of its divisors is an integer number (21059235).

Almost surely, 2^84216709 is an apocalyptic number.

It is an amenable number.

84216709 is a deficient number, since it is larger than the sum of its proper divisors (20231).

84216709 is a wasteful number, since it uses less digits than its factorization.

84216709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20230.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 84216709 is about 9176.9662198354. The cubic root of 84216709 is about 438.3282101049.

The spelling of 84216709 in words is "eighty-four million, two hundred sixteen thousand, seven hundred nine".