721312236 has 24 divisors (see below), whose sum is σ = 1870069040. Its totient is φ = 240437376.

The previous prime is 721312231. The next prime is 721312237. The reversal of 721312236 is 632213127.

It is a super-3 number, since 3×721312236³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (721312231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3339301 + ... + 3339516.

Almost surely, 2^721312236 is an apocalyptic number.

It is an amenable number.

721312236 is an abundant number, since it is smaller than the sum of its proper divisors (1148756804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721312236 is a wasteful number, since it uses less digits than its factorization.

721312236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6678830 (or 6678822 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 721312236 is about 26857.2566730111. The cubic root of 721312236 is about 896.8251244645.

The spelling of 721312236 in words is "seven hundred twenty-one million, three hundred twelve thousand, two hundred thirty-six".