8721432 has 80 divisors (see below), whose sum is σ = 25076040. Its totient is φ = 2830464.

The previous prime is 8721413. The next prime is 8721443. The reversal of 8721432 is 2341278.

It is a super-2 number, since 2×8721432² = 152126752261248, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 8721396 and 8721405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 27708 + ... + 28020.

Almost surely, 2^8721432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8721432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12538020).

8721432 is an abundant number, since it is smaller than the sum of its proper divisors (16354608).

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

8721432 is a wasteful number, since it uses less digits than its factorization.

8721432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374 (or 361 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 8721432 is about 2953.2070702882. The cubic root of 8721432 is about 205.8397597619.

It can be divided in two parts, 872 and 1432, that added together give a square (2304 = 48²).

The spelling of 8721432 in words is "eight million, seven hundred twenty-one thousand, four hundred thirty-two".