1968664354281 has 135 divisors (see below), whose sum is σ = 3134088754797. Its totient is φ = 1231464908880.

The previous prime is 1968664354273. The next prime is 1968664354291. The reversal of 1968664354281 is 1824534668691.

The square root of 1968664354281 is 1403091.

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

1968664354281 is a `hidden beast` number, since 1 + 9 + 6 + 8 + 6 + 6 + 4 + 3 + 542 + 81 = 666.

It is not a de Polignac number, because 1968664354281 - 2³ = 1968664354273 is a prime.

It is a super-2 number, since 2×1968664354281² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1968664354291) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 18398732230 + ... + 18398732336.

Almost surely, 2^{1968664354281} is an apocalyptic number.

1968664354281 is the 1403091-st square number.

1968664354281 is the 701546-th centered octagonal number.

It is an amenable number.

1968664354281 is a deficient number, since it is larger than the sum of its proper divisors (1165424400516).

1968664354281 is an frugal number, since it uses more digits than its factorization.

1968664354281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 188 counting only the distinct ones).

The product of its digits is 59719680, while the sum is 63.

The spelling of 1968664354281 in words is "one trillion, nine hundred sixty-eight billion, six hundred sixty-four million, three hundred fifty-four thousand, two hundred eighty-one".