73671821 has 4 divisors (see below), whose sum is σ = 73704444. Its totient is φ = 73639200.

The previous prime is 73671809. The next prime is 73671833. The reversal of 73671821 is 12817637.

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

It is an interprime number because it is at equal distance from previous prime (73671809) and next prime (73671833).

It can be written as a sum of positive squares in 2 ways, for example, as 18748900 + 54922921 = 4330^2 + 7411^2 .

It is a cyclic number.

It is not a de Polignac number, because 73671821 - 2¹⁴ = 73655437 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73676821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12650 + ... + 17531.

It is an arithmetic number, because the mean of its divisors is an integer number (18426111).

Almost surely, 2^73671821 is an apocalyptic number.

It is an amenable number.

73671821 is a deficient number, since it is larger than the sum of its proper divisors (32623).

73671821 is a wasteful number, since it uses less digits than its factorization.

73671821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32622.

The product of its digits is 14112, while the sum is 35.

The square root of 73671821 is about 8583.2290543827. The cubic root of 73671821 is about 419.2120923717.

The spelling of 73671821 in words is "seventy-three million, six hundred seventy-one thousand, eight hundred twenty-one".