72145872 has 30 divisors (see below), whose sum is σ = 201908642. Its totient is φ = 24048576.

The previous prime is 72145817. The next prime is 72145877. The reversal of 72145872 is 27854127.

72145872 is a `hidden beast` number, since 72 + 1 + 4 + 587 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 36433296 + 35712576 = 6036^2 + 5976^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72145877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 250363 + ... + 250650.

Almost surely, 2^72145872 is an apocalyptic number.

72145872 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

72145872 is an abundant number, since it is smaller than the sum of its proper divisors (129762770).

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

72145872 is a wasteful number, since it uses less digits than its factorization.

72145872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501027 (or 501018 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 72145872 is about 8493.8726150090. The cubic root of 72145872 is about 416.2975250771.

Adding to 72145872 its reverse (27854127), we get a palindrome (99999999).

The spelling of 72145872 in words is "seventy-two million, one hundred forty-five thousand, eight hundred seventy-two".