72727272 has 96 divisors (see below), whose sum is σ = 203116680. Its totient is φ = 23500800.

The previous prime is 72727247. The next prime is 72727301. The reversal of 72727272 is 27272727.

It can be written as a sum of positive squares in 4 ways, for example, as 72692676 + 34596 = 8526^2 + 186^2 .

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.

72727272 is an undulating number in base 10.

72727272 is a modest number, since divided by 727272 gives 72 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 530788 + ... + 530924.

Almost surely, 2^72727272 is an apocalyptic number.

72727272 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72727272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101558340).

72727272 is an abundant number, since it is smaller than the sum of its proper divisors (130389408).

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

72727272 is a wasteful number, since it uses less digits than its factorization.

72727272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323 (or 316 counting only the distinct ones).

The product of its digits is 38416, while the sum is 36.

The square root of 72727272 is about 8528.0286115843. The cubic root of 72727272 is about 417.4128030933.

72727272 divided by its sum of digits (36) gives a palindrome (2020202).

Adding to 72727272 its reverse (27272727), we get a palindrome (99999999).

The spelling of 72727272 in words is "seventy-two million, seven hundred twenty-seven thousand, two hundred seventy-two".