72645280 has 24 divisors (see below), whose sum is σ = 171624852. Its totient is φ = 29058048.

The previous prime is 72645277. The next prime is 72645289. The reversal of 72645280 is 8254627.

It can be written as a sum of positive squares in 2 ways, for example, as 69155856 + 3489424 = 8316^2 + 1868^2 .

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (72645289) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 226857 + ... + 227176.

Almost surely, 2^72645280 is an apocalyptic number.

It is an amenable number.

72645280 is an abundant number, since it is smaller than the sum of its proper divisors (98979572).

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

72645280 is a wasteful number, since it uses less digits than its factorization.

72645280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454048 (or 454040 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 72645280 is about 8523.2200487844. The cubic root of 72645280 is about 417.2558817664.

It can be divided in two parts, 7264 and 5280, that added together give a square (12544 = 112²).

The spelling of 72645280 in words is "seventy-two million, six hundred forty-five thousand, two hundred eighty".