72781807 has 12 divisors (see below), whose sum is σ = 85447560. Its totient is φ = 61807536.

The previous prime is 72781783. The next prime is 72781829. The reversal of 72781807 is 70818727.

It is a happy number.

It is not a de Polignac number, because 72781807 - 2⁷ = 72781679 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72781807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72781207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1473 + ... + 12154.

It is an arithmetic number, because the mean of its divisors is an integer number (7120630).

Almost surely, 2^72781807 is an apocalyptic number.

72781807 is a deficient number, since it is larger than the sum of its proper divisors (12665753).

72781807 is a wasteful number, since it uses less digits than its factorization.

72781807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13750 (or 13743 counting only the distinct ones).

The product of its (nonzero) digits is 43904, while the sum is 40.

The square root of 72781807 is about 8531.2254102210. The cubic root of 72781807 is about 417.5171102266.

The spelling of 72781807 in words is "seventy-two million, seven hundred eighty-one thousand, eight hundred seven".