72931897 has 4 divisors (see below), whose sum is σ = 75446820. Its totient is φ = 70416976.

The previous prime is 72931889. The next prime is 72931967. The reversal of 72931897 is 79813927.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79813927 = 19 ⋅4200733.

It can be written as a sum of positive squares in 2 ways, for example, as 45306361 + 27625536 = 6731^2 + 5256^2 .

It is a cyclic number.

It is not a de Polignac number, because 72931897 - 2³ = 72931889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72931867) 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 3 ways as a sum of consecutive naturals, for example, 1257418 + ... + 1257475.

It is an arithmetic number, because the mean of its divisors is an integer number (18861705).

Almost surely, 2^72931897 is an apocalyptic number.

It is an amenable number.

72931897 is a deficient number, since it is larger than the sum of its proper divisors (2514923).

72931897 is a wasteful number, since it uses less digits than its factorization.

72931897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2514922.

The product of its digits is 190512, while the sum is 46.

The square root of 72931897 is about 8540.0173887411. The cubic root of 72931897 is about 417.8039132025.

The spelling of 72931897 in words is "seventy-two million, nine hundred thirty-one thousand, eight hundred ninety-seven".