72861984 has 144 divisors (see below), whose sum is σ = 230580000. Its totient is φ = 22374144.

The previous prime is 72861967. The next prime is 72862001. The reversal of 72861984 is 48916827.

72861984 is a `hidden beast` number, since 7 + 28 + 619 + 8 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (72861967) and next prime (72862001).

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 145767 + ... + 146265.

It is an arithmetic number, because the mean of its divisors is an integer number (1601250).

Almost surely, 2^72861984 is an apocalyptic number.

72861984 is the 4563-rd nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72861984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115290000).

72861984 is an abundant number, since it is smaller than the sum of its proper divisors (157718016).

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

72861984 is a wasteful number, since it uses less digits than its factorization.

72861984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544 (or 517 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 72861984 is about 8535.9231486700. The cubic root of 72861984 is about 417.6703673204.

The spelling of 72861984 in words is "seventy-two million, eight hundred sixty-one thousand, nine hundred eighty-four".