72001613 has 16 divisors (see below), whose sum is σ = 78323760. Its totient is φ = 65934336.

The previous prime is 72001591. The next prime is 72001639. The reversal of 72001613 is 31610027.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 7327849 + 64673764 = 2707^2 + 8042^2 .

It is a cyclic number.

It is not a de Polignac number, because 72001613 - 2¹⁴ = 71985229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72001663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141203 + ... + 141711.

It is an arithmetic number, because the mean of its divisors is an integer number (4895235).

Almost surely, 2^72001613 is an apocalyptic number.

It is an amenable number.

72001613 is a deficient number, since it is larger than the sum of its proper divisors (6322147).

72001613 is a wasteful number, since it uses less digits than its factorization.

72001613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 736.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 72001613 is about 8485.3764206428. The cubic root of 72001613 is about 416.0198712309.

The spelling of 72001613 in words is "seventy-two million, one thousand, six hundred thirteen".