72021432 has 64 divisors (see below), whose sum is σ = 212428800. Its totient is φ = 19912320.

The previous prime is 72021373. The next prime is 72021473. The reversal of 72021432 is 23412027.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 72021399 and 72021408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1707 + ... + 12122.

It is an arithmetic number, because the mean of its divisors is an integer number (3319200).

Almost surely, 2^72021432 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 72021432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106214400).

72021432 is an abundant number, since it is smaller than the sum of its proper divisors (140407368).

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

72021432 is a wasteful number, since it uses less digits than its factorization.

72021432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13876 (or 13872 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 72021432 is about 8486.5441729835. The cubic root of 72021432 is about 416.0580386232.

Adding to 72021432 its reverse (23412027), we get a palindrome (95433459).

The spelling of 72021432 in words is "seventy-two million, twenty-one thousand, four hundred thirty-two".