72920217 has 8 divisors (see below), whose sum is σ = 99488224. Its totient is φ = 47482848.

The previous prime is 72920207. The next prime is 72920227. The reversal of 72920217 is 71202927.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (72920207) and next prime (72920227).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 72920217 - 2⁸ = 72919961 is a prime.

It is a super-3 number, since 3×72920217³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72920207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282508 + ... + 282765.

It is an arithmetic number, because the mean of its divisors is an integer number (12436028).

Almost surely, 2^72920217 is an apocalyptic number.

It is an amenable number.

72920217 is a deficient number, since it is larger than the sum of its proper divisors (26568007).

72920217 is a wasteful number, since it uses less digits than its factorization.

72920217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565319.

The product of its (nonzero) digits is 3528, while the sum is 30.

The square root of 72920217 is about 8539.3335220028. Note that the first 3 decimals coincide. The cubic root of 72920217 is about 417.7816083289.

It can be divided in two parts, 72920 and 217, that added together give a palindrome (73137).

The spelling of 72920217 in words is "seventy-two million, nine hundred twenty thousand, two hundred seventeen".