66258878464 has 45 divisors (see below), whose sum is σ = 132579640011. Its totient is φ = 33112965120.

The previous prime is 66258878453. The next prime is 66258878551. The reversal of 66258878464 is 46487885266.

The square root of 66258878464 is 257408.

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

It is a Harshad number since it is a multiple of its sum of digits (64).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66258878396 and 66258878405.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 32947219 + ... + 32949229.

Almost surely, 2^66258878464 is an apocalyptic number.

66258878464 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

66258878464 is the 257408-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66258878464

66258878464 is an abundant number, since it is smaller than the sum of its proper divisors (66320761547).

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

66258878464 is an frugal number, since it uses more digits than its factorization.

66258878464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4050 (or 2013 counting only the distinct ones).

The product of its digits is 123863040, while the sum is 64.

Multiplying 66258878464 by its sum of digits (64), we get a square (4240568221696 = 2059264²).

66258878464 divided by its sum of digits (64) gives a square (1035294976 = 32176²).

The spelling of 66258878464 in words is "sixty-six billion, two hundred fifty-eight million, eight hundred seventy-eight thousand, four hundred sixty-four".