216738664704 has 405 divisors, whose sum is σ = 669674804799. Its totient is φ = 69721067520.

The previous prime is 216738664633. The next prime is 216738664729. The reversal of 216738664704 is 407466837612.

The square root of 216738664704 is 465552.

It is a perfect power (a square), and thus also a powerful number.

216738664704 is a `hidden beast` number, since 2 + 167 + 3 + 8 + 6 + 6 + 470 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 29118009600 + 187620655104 = 170640^2 + 433152^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 3553092834 + ... + 3553092894.

Almost surely, 2^216738664704 is an apocalyptic number.

216738664704 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

216738664704 is the 465552-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216738664704

216738664704 is an abundant number, since it is smaller than the sum of its proper divisors (452936140095).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216738664704 is an frugal number, since it uses more digits than its factorization.

216738664704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 8128512, while the sum is 54.

The spelling of 216738664704 in words is "two hundred sixteen billion, seven hundred thirty-eight million, six hundred sixty-four thousand, seven hundred four".