73928021 has 4 divisors (see below), whose sum is σ = 74104044. Its totient is φ = 73752000.

The previous prime is 73927999. The next prime is 73928033. The reversal of 73928021 is 12082937.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9302500 + 64625521 = 3050^2 + 8039^2 .

It is a cyclic number.

It is not a de Polignac number, because 73928021 - 2¹⁸ = 73665877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73928081) 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, 87380 + ... + 88221.

It is an arithmetic number, because the mean of its divisors is an integer number (18526011).

Almost surely, 2^73928021 is an apocalyptic number.

It is an amenable number.

73928021 is a deficient number, since it is larger than the sum of its proper divisors (176023).

73928021 is a wasteful number, since it uses less digits than its factorization.

73928021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176022.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 73928021 is about 8598.1405547944. The cubic root of 73928021 is about 419.6974786726.

The spelling of 73928021 in words is "seventy-three million, nine hundred twenty-eight thousand, twenty-one".