72991727 has 4 divisors (see below), whose sum is σ = 77285376. Its totient is φ = 68698080.

The previous prime is 72991703. The next prime is 72991733. The reversal of 72991727 is 72719927.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 72719927 = 7 ⋅10388561.

It is a cyclic number.

It is not a de Polignac number, because 72991727 - 2⁶ = 72991663 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 (72991747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2146799 + ... + 2146832.

It is an arithmetic number, because the mean of its divisors is an integer number (19321344).

Almost surely, 2^72991727 is an apocalyptic number.

72991727 is a deficient number, since it is larger than the sum of its proper divisors (4293649).

72991727 is a wasteful number, since it uses less digits than its factorization.

72991727 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4293648.

The product of its digits is 111132, while the sum is 44.

The square root of 72991727 is about 8543.5195908946. The cubic root of 72991727 is about 417.9181310631.

The spelling of 72991727 in words is "seventy-two million, nine hundred ninety-one thousand, seven hundred twenty-seven".