220644863451 has 18 divisors (see below), whose sum is σ = 320011385148. Its totient is φ = 146495709000.

The previous prime is 220644863437. The next prime is 220644863503. The reversal of 220644863451 is 154368446022.

220644863451 is a `hidden beast` number, since 2 + 2 + 0 + 6 + 4 + 4 + 8 + 634 + 5 + 1 = 666.

It is not a de Polignac number, because 220644863451 - 2¹⁵ = 220644830683 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 220644863397 and 220644863406.

It is not an unprimeable number, because it can be changed into a prime (220644883451) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 22320756 + ... + 22330638.

It is an arithmetic number, because the mean of its divisors is an integer number (17778410286).

Almost surely, 2^220644863451 is an apocalyptic number.

220644863451 is a deficient number, since it is larger than the sum of its proper divisors (99366521697).

220644863451 is an frugal number, since it uses more digits than its factorization.

220644863451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20023 (or 10137 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 45.

The spelling of 220644863451 in words is "two hundred twenty billion, six hundred forty-four million, eight hundred sixty-three thousand, four hundred fifty-one".