72644420 has 48 divisors (see below), whose sum is σ = 158760000. Its totient is φ = 27888000.

The previous prime is 72644393. The next prime is 72644443. The reversal of 72644420 is 2444627.

It is a Harshad number since it is a multiple of its sum of digits (29).

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, 145331 + ... + 145829.

It is an arithmetic number, because the mean of its divisors is an integer number (3307500).

Almost surely, 2^72644420 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 72644420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79380000).

72644420 is an abundant number, since it is smaller than the sum of its proper divisors (86115580).

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

72644420 is a wasteful number, since it uses less digits than its factorization.

72644420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 788 (or 786 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 29.

The square root of 72644420 is about 8523.1695982187. The cubic root of 72644420 is about 417.2542352200.

The spelling of 72644420 in words is "seventy-two million, six hundred forty-four thousand, four hundred twenty".