72031553 has 4 divisors (see below), whose sum is σ = 78579888. Its totient is φ = 65483220.

The previous prime is 72031549. The next prime is 72031571. The reversal of 72031553 is 35513027.

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: 35513027 = 11 ⋅3228457.

It is not a de Polignac number, because 72031553 - 2² = 72031549 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72031513) 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 3 ways as a sum of consecutive naturals, for example, 3274151 + ... + 3274172.

It is an arithmetic number, because the mean of its divisors is an integer number (19644972).

Almost surely, 2^72031553 is an apocalyptic number.

It is an amenable number.

72031553 is a deficient number, since it is larger than the sum of its proper divisors (6548335).

72031553 is a wasteful number, since it uses less digits than its factorization.

72031553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6548334.

The product of its (nonzero) digits is 3150, while the sum is 26.

The square root of 72031553 is about 8487.1404489380. The cubic root of 72031553 is about 416.0775269249.

The spelling of 72031553 in words is "seventy-two million, thirty-one thousand, five hundred fifty-three".