73131821 has 8 divisors (see below), whose sum is σ = 86275584. Its totient is φ = 60662160.

The previous prime is 73131811. The next prime is 73131827. The reversal of 73131821 is 12813137.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73131821 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 (73131827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 168290 + ... + 168723.

It is an arithmetic number, because the mean of its divisors is an integer number (10784448).

Almost surely, 2^73131821 is an apocalyptic number.

It is an amenable number.

73131821 is a deficient number, since it is larger than the sum of its proper divisors (13143763).

73131821 is a wasteful number, since it uses less digits than its factorization.

73131821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337051.

The product of its digits is 1008, while the sum is 26.

The square root of 73131821 is about 8551.7145064601. The cubic root of 73131821 is about 418.1853321452.

Adding to 73131821 its reverse (12813137), we get a palindrome (85944958).

The spelling of 73131821 in words is "seventy-three million, one hundred thirty-one thousand, eight hundred twenty-one".