72781911 has 6 divisors (see below), whose sum is σ = 105129440. Its totient is φ = 48521268.

The previous prime is 72781889. The next prime is 72781921. The reversal of 72781911 is 11918727.

It is not a de Polignac number, because 72781911 - 2⁷ = 72781783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72781921) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4043431 + ... + 4043448.

Almost surely, 2^72781911 is an apocalyptic number.

72781911 is a deficient number, since it is larger than the sum of its proper divisors (32347529).

72781911 is a wasteful number, since it uses less digits than its factorization.

72781911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8086885 (or 8086882 counting only the distinct ones).

The product of its digits is 7056, while the sum is 36.

The square root of 72781911 is about 8531.2315054745. The cubic root of 72781911 is about 417.5173090939.

The spelling of 72781911 in words is "seventy-two million, seven hundred eighty-one thousand, nine hundred eleven".