72821383 has 4 divisors (see below), whose sum is σ = 72854208. Its totient is φ = 72788560.

The previous prime is 72821339. The next prime is 72821393. The reversal of 72821383 is 38312827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38312827 = 7 ⋅5473261.

It is a cyclic number.

It is not a de Polignac number, because 72821383 - 2⁹ = 72820871 is a prime.

It is a super-4 number, since 4×72821383⁴ (a number of 33 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72821393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12823 + ... + 17608.

It is an arithmetic number, because the mean of its divisors is an integer number (18213552).

Almost surely, 2^72821383 is an apocalyptic number.

72821383 is a deficient number, since it is larger than the sum of its proper divisors (32825).

72821383 is a wasteful number, since it uses less digits than its factorization.

72821383 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32824.

The product of its digits is 16128, while the sum is 34.

The square root of 72821383 is about 8533.5445742083. The cubic root of 72821383 is about 417.5927731968.

The spelling of 72821383 in words is "seventy-two million, eight hundred twenty-one thousand, three hundred eighty-three".