72021361 has 2 divisors, whose sum is σ = 72021362. Its totient is φ = 72021360.

The previous prime is 72021347. The next prime is 72021371. The reversal of 72021361 is 16312027.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41152225 + 30869136 = 6415^2 + 5556^2 .

It is a cyclic number.

It is not a de Polignac number, because 72021361 - 2¹⁵ = 71988593 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72021331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36010680 + 36010681.

It is an arithmetic number, because the mean of its divisors is an integer number (36010681).

Almost surely, 2^72021361 is an apocalyptic number.

It is an amenable number.

72021361 is a deficient number, since it is larger than the sum of its proper divisors (1).

72021361 is an equidigital number, since it uses as much as digits as its factorization.

72021361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 72021361 is about 8486.5399898899. The cubic root of 72021361 is about 416.0579019041.

Adding to 72021361 its reverse (16312027), we get a palindrome (88333388).

The spelling of 72021361 in words is "seventy-two million, twenty-one thousand, three hundred sixty-one".