73145221 has 8 divisors (see below), whose sum is σ = 78958080. Its totient is φ = 67551792.

The previous prime is 73145209. The next prime is 73145251. The reversal of 73145221 is 12254137.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 73145221 - 2¹¹ = 73143173 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73145251) 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, 54165 + ... + 55498.

It is an arithmetic number, because the mean of its divisors is an integer number (9869760).

Almost surely, 2^73145221 is an apocalyptic number.

It is an amenable number.

73145221 is a deficient number, since it is larger than the sum of its proper divisors (5812859).

73145221 is a wasteful number, since it uses less digits than its factorization.

73145221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109715.

The product of its digits is 1680, while the sum is 25.

The square root of 73145221 is about 8552.4979391988. The cubic root of 73145221 is about 418.2108720591.

Adding to 73145221 its reverse (12254137), we get a palindrome (85399358).

The spelling of 73145221 in words is "seventy-three million, one hundred forty-five thousand, two hundred twenty-one".