731664121 has 4 divisors (see below), whose sum is σ = 731808000. Its totient is φ = 731520244.

The previous prime is 731664119. The next prime is 731664137. The reversal of 731664121 is 121466137.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 731664121 - 2¹ = 731664119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (731664151) 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, 64021 + ... + 74578.

It is an arithmetic number, because the mean of its divisors is an integer number (182952000).

Almost surely, 2^731664121 is an apocalyptic number.

It is an amenable number.

731664121 is a deficient number, since it is larger than the sum of its proper divisors (143879).

731664121 is a wasteful number, since it uses less digits than its factorization.

731664121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143878.

The product of its digits is 6048, while the sum is 31.

The square root of 731664121 is about 27049.2905821946. The cubic root of 731664121 is about 901.0950132679.

The spelling of 731664121 in words is "seven hundred thirty-one million, six hundred sixty-four thousand, one hundred twenty-one".