72814981 has 4 divisors (see below), whose sum is σ = 72855072. Its totient is φ = 72774892.

The previous prime is 72814967. The next prime is 72814991. The reversal of 72814981 is 18941827.

It is a happy number.

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: 18941827 = 3167 ⋅5981.

It is a cyclic number.

It is not a de Polignac number, because 72814981 - 2⁵ = 72814949 is a prime.

It is a super-2 number, since 2×72814981² = 10604042916060722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72814921) 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, 17185 + ... + 20998.

It is an arithmetic number, because the mean of its divisors is an integer number (18213768).

Almost surely, 2^72814981 is an apocalyptic number.

It is an amenable number.

72814981 is a deficient number, since it is larger than the sum of its proper divisors (40091).

72814981 is a wasteful number, since it uses less digits than its factorization.

72814981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40090.

The product of its digits is 32256, while the sum is 40.

The square root of 72814981 is about 8533.1694580619. The cubic root of 72814981 is about 417.5805354576.

The spelling of 72814981 in words is "seventy-two million, eight hundred fourteen thousand, nine hundred eighty-one".