72736021 has 8 divisors (see below), whose sum is σ = 74101824. Its totient is φ = 71379840.

The previous prime is 72735997. The next prime is 72736039. The reversal of 72736021 is 12063727.

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-72736021 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 (72736061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13861 + ... + 18373.

It is an arithmetic number, because the mean of its divisors is an integer number (9262728).

Almost surely, 2^72736021 is an apocalyptic number.

72736021 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

72736021 is a deficient number, since it is larger than the sum of its proper divisors (1365803).

72736021 is a wasteful number, since it uses less digits than its factorization.

72736021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4811.

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 72736021 is about 8528.5415517543. The cubic root of 72736021 is about 417.4295405018.

Adding to 72736021 its reverse (12063727), we get a palindrome (84799748).

The spelling of 72736021 in words is "seventy-two million, seven hundred thirty-six thousand, twenty-one".