72918901225 has 27 divisors (see below), whose sum is σ = 92248181893. Its totient is φ = 57178291040.

The previous prime is 72918901217. The next prime is 72918901229. The reversal of 72918901225 is 52210981927.

The square root of 72918901225 is 270035.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 549292969 + 72369608256 = 23437^2 + 269016^2 .

It is not a de Polignac number, because 72918901225 - 2³ = 72918901217 is a prime.

It is a super-2 number, since 2×72918901225² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72918901229) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 71558766 + ... + 71559784.

Almost surely, 2^72918901225 is an apocalyptic number.

72918901225 is the 270035-th square number.

72918901225 is the 135018-th centered octagonal number.

It is an amenable number.

72918901225 is a deficient number, since it is larger than the sum of its proper divisors (19329280668).

72918901225 is an frugal number, since it uses more digits than its factorization.

72918901225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2154 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 46.

The spelling of 72918901225 in words is "seventy-two billion, nine hundred eighteen million, nine hundred one thousand, two hundred twenty-five".