218721452 has 6 divisors (see below), whose sum is σ = 382762548. Its totient is φ = 109360724.

The previous prime is 218721449. The next prime is 218721457. The reversal of 218721452 is 254127812.

218721452 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (218721457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27340178 + ... + 27340185.

It is an arithmetic number, because the mean of its divisors is an integer number (63793758).

Almost surely, 2^218721452 is an apocalyptic number.

It is an amenable number.

218721452 is a deficient number, since it is larger than the sum of its proper divisors (164041096).

218721452 is a wasteful number, since it uses less digits than its factorization.

218721452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54680367 (or 54680365 counting only the distinct ones).

The product of its digits is 8960, while the sum is 32.

The square root of 218721452 is about 14789.2343277128. The cubic root of 218721452 is about 602.5093535734.

The spelling of 218721452 in words is "two hundred eighteen million, seven hundred twenty-one thousand, four hundred fifty-two".