721812147 has 32 divisors (see below), whose sum is σ = 1184747520. Its totient is φ = 381659040.

The previous prime is 721812139. The next prime is 721812149. The reversal of 721812147 is 741218127.

It is not a de Polignac number, because 721812147 - 2³ = 721812139 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (721812149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3879 + ... + 38192.

It is an arithmetic number, because the mean of its divisors is an integer number (37023360).

Almost surely, 2^721812147 is an apocalyptic number.

721812147 is a deficient number, since it is larger than the sum of its proper divisors (462935373).

721812147 is a wasteful number, since it uses less digits than its factorization.

721812147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42143.

The product of its digits is 6272, while the sum is 33.

The square root of 721812147 is about 26866.5618753126. The cubic root of 721812147 is about 897.0322604724.

The spelling of 721812147 in words is "seven hundred twenty-one million, eight hundred twelve thousand, one hundred forty-seven".