84386640 has 320 divisors, whose sum is σ = 313479936. Its totient is φ = 18579456.

The previous prime is 84386633. The next prime is 84386641. The reversal of 84386640 is 4668348.

It is a super-2 number, since 2×84386640² = 14242210020979200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84386641) 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 63 ways as a sum of consecutive naturals, for example, 1962459 + ... + 1962501.

Almost surely, 2^84386640 is an apocalyptic number.

84386640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

84386640 is the 5304-th octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84386640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156739968).

84386640 is an abundant number, since it is smaller than the sum of its proper divisors (229093296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

84386640 is a wasteful number, since it uses less digits than its factorization.

84386640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 39.

The square root of 84386640 is about 9186.2201149330. The cubic root of 84386640 is about 438.6228290291.

The spelling of 84386640 in words is "eighty-four million, three hundred eighty-six thousand, six hundred forty".