216626451 has 4 divisors (see below), whose sum is σ = 288835272. Its totient is φ = 144417632.

The previous prime is 216626413. The next prime is 216626471. The reversal of 216626451 is 154626612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216626451 - 2⁷ = 216626323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216626471) 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, 36104406 + ... + 36104411.

It is an arithmetic number, because the mean of its divisors is an integer number (72208818).

Almost surely, 2^216626451 is an apocalyptic number.

216626451 is a deficient number, since it is larger than the sum of its proper divisors (72208821).

216626451 is an equidigital number, since it uses as much as digits as its factorization.

216626451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72208820.

The product of its digits is 17280, while the sum is 33.

The square root of 216626451 is about 14718.2353222117. The cubic root of 216626451 is about 600.5794873660.

The spelling of 216626451 in words is "two hundred sixteen million, six hundred twenty-six thousand, four hundred fifty-one".