72513553 has 4 divisors (see below), whose sum is σ = 82872640. Its totient is φ = 62154468.

The previous prime is 72513521. The next prime is 72513559. The reversal of 72513553 is 35531527.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 35531527 = 23 ⋅1544849.

It is a cyclic number.

It is not a de Polignac number, because 72513553 - 2⁵ = 72513521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72513559) 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, 5179533 + ... + 5179546.

It is an arithmetic number, because the mean of its divisors is an integer number (20718160).

Almost surely, 2^72513553 is an apocalyptic number.

It is an amenable number.

72513553 is a deficient number, since it is larger than the sum of its proper divisors (10359087).

72513553 is a wasteful number, since it uses less digits than its factorization.

72513553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10359086.

The product of its digits is 15750, while the sum is 31.

The square root of 72513553 is about 8515.4890053361. The cubic root of 72513553 is about 417.0035271245.

The spelling of 72513553 in words is "seventy-two million, five hundred thirteen thousand, five hundred fifty-three".