72097081 has 9 divisors (see below), whose sum is σ = 83937231. Its totient is φ = 61746552.

The previous prime is 72097079. The next prime is 72097097. The reversal of 72097081 is 18079027.

The square root of 72097081 is 8491.

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

It can be written as a sum of positive squares in only one way, i.e., 2941225 + 69155856 = 1715^2 + 8316^2 .

It is not a de Polignac number, because 72097081 - 2¹ = 72097079 is a prime.

It is a super-2 number, since 2×72097081² = 10395978177441122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72097061) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 58831 + ... + 60043.

It is an arithmetic number, because the mean of its divisors is an integer number (9326359).

Almost surely, 2^72097081 is an apocalyptic number.

72097081 is the 8491-st square number.

72097081 is the 4246-th centered octagonal number.

It is an amenable number.

72097081 is a deficient number, since it is larger than the sum of its proper divisors (11840150).

72097081 is an frugal number, since it uses more digits than its factorization.

72097081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2440 (or 1220 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 34.

The cubic root of 72097081 is about 416.2036589857.

Multiplying 72097081 by its product of nonzero digits (7056), we get a square (508717003536 = 713244²).

The spelling of 72097081 in words is "seventy-two million, ninety-seven thousand, eighty-one".