84216381 has 4 divisors (see below), whose sum is σ = 112288512. Its totient is φ = 56144252.

The previous prime is 84216371. The next prime is 84216397. The reversal of 84216381 is 18361248.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 84216381 - 2¹⁸ = 83954237 is a prime.

It is a super-2 number, since 2×84216381² = 14184797657474322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84216361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14036061 + ... + 14036066.

It is an arithmetic number, because the mean of its divisors is an integer number (28072128).

Almost surely, 2^84216381 is an apocalyptic number.

It is an amenable number.

84216381 is a deficient number, since it is larger than the sum of its proper divisors (28072131).

84216381 is a wasteful number, since it uses less digits than its factorization.

84216381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28072130.

The product of its digits is 9216, while the sum is 33.

The square root of 84216381 is about 9176.9483489883. The cubic root of 84216381 is about 438.3276410498.

The spelling of 84216381 in words is "eighty-four million, two hundred sixteen thousand, three hundred eighty-one".