73929721 has 4 divisors (see below), whose sum is σ = 74469492. Its totient is φ = 73389952.

The previous prime is 73929707. The next prime is 73929727. The reversal of 73929721 is 12792937.

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 45414121 + 28515600 = 6739^2 + 5340^2 .

It is a cyclic number.

It is not a de Polignac number, because 73929721 - 2²¹ = 71832569 is a prime.

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 not an unprimeable number, because it can be changed into a prime (73929727) 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, 269680 + ... + 269953.

It is an arithmetic number, because the mean of its divisors is an integer number (18617373).

Almost surely, 2^73929721 is an apocalyptic number.

It is an amenable number.

73929721 is a deficient number, since it is larger than the sum of its proper divisors (539771).

73929721 is a wasteful number, since it uses less digits than its factorization.

73929721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539770.

The product of its digits is 47628, while the sum is 40.

The square root of 73929721 is about 8598.2394128100. The cubic root of 73929721 is about 419.7006956767.

The spelling of 73929721 in words is "seventy-three million, nine hundred twenty-nine thousand, seven hundred twenty-one".