72127691 has 4 divisors (see below), whose sum is σ = 72212712. Its totient is φ = 72042672.

The previous prime is 72127673. The next prime is 72127721. The reversal of 72127691 is 19672127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19672127 = 3137 ⋅6271.

It is a cyclic number.

It is not a de Polignac number, because 72127691 - 2¹⁴ = 72111307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72127621) 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, 41225 + ... + 42938.

It is an arithmetic number, because the mean of its divisors is an integer number (18053178).

Almost surely, 2^72127691 is an apocalyptic number.

72127691 is a deficient number, since it is larger than the sum of its proper divisors (85021).

72127691 is an equidigital number, since it uses as much as digits as its factorization.

72127691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85020.

The product of its digits is 10584, while the sum is 35.

The square root of 72127691 is about 8492.8023054820. The cubic root of 72127691 is about 416.2625526850.

The spelling of 72127691 in words is "seventy-two million, one hundred twenty-seven thousand, six hundred ninety-one".