72464640 has 144 divisors (see below), whose sum is σ = 234880128. Its totient is φ = 19038208.

The previous prime is 72464633. The next prime is 72464641. The reversal of 72464640 is 4646427.

It is a super-2 number, since 2×72464640² = 10502248100659200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72464641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 433837 + ... + 434003.

It is an arithmetic number, because the mean of its divisors is an integer number (1631112).

Almost surely, 2^72464640 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 72464640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117440064).

72464640 is an abundant number, since it is smaller than the sum of its proper divisors (162415488).

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

72464640 is a wasteful number, since it uses less digits than its factorization.

72464640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304 (or 290 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 33.

The square root of 72464640 is about 8512.6165190263. The cubic root of 72464640 is about 416.9097447415.

The spelling of 72464640 in words is "seventy-two million, four hundred sixty-four thousand, six hundred forty".