72115421 has 8 divisors (see below), whose sum is σ = 82471104. Its totient is φ = 61773120.

The previous prime is 72115409. The next prime is 72115423. The reversal of 72115421 is 12451127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72115421 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 (72115423) 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 7 ways as a sum of consecutive naturals, for example, 14741 + ... + 19013.

It is an arithmetic number, because the mean of its divisors is an integer number (10308888).

Almost surely, 2^72115421 is an apocalyptic number.

It is an amenable number.

72115421 is a deficient number, since it is larger than the sum of its proper divisors (10355683).

72115421 is a wasteful number, since it uses less digits than its factorization.

72115421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6691.

The product of its digits is 560, while the sum is 23.

The square root of 72115421 is about 8492.0798983523. The cubic root of 72115421 is about 416.2389471825.

Adding to 72115421 its reverse (12451127), we get a palindrome (84566548).

The spelling of 72115421 in words is "seventy-two million, one hundred fifteen thousand, four hundred twenty-one".