863453721 has 16 divisors (see below), whose sum is σ = 1240386560. Its totient is φ = 531118080.

The previous prime is 863453699. The next prime is 863453729. The reversal of 863453721 is 127354368.

863453721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 863453721 - 2⁹ = 863453209 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 863453721.

It is not an unprimeable number, because it can be changed into a prime (863453729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128985 + ... + 135513.

It is an arithmetic number, because the mean of its divisors is an integer number (77524160).

Almost surely, 2^863453721 is an apocalyptic number.

It is an amenable number.

863453721 is a deficient number, since it is larger than the sum of its proper divisors (376932839).

863453721 is a wasteful number, since it uses less digits than its factorization.

863453721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9936.

The product of its digits is 120960, while the sum is 39.

The square root of 863453721 is about 29384.5830496197. The cubic root of 863453721 is about 952.2398564857.

The spelling of 863453721 in words is "eight hundred sixty-three million, four hundred fifty-three thousand, seven hundred twenty-one".