166878786064 has 45 divisors (see below), whose sum is σ = 328051957293. Its totient is φ = 82237562496.

The previous prime is 166878786049. The next prime is 166878786079. The reversal of 166878786064 is 460687878661.

The square root of 166878786064 is 408508.

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

It is an interprime number because it is at equal distance from previous prime (166878786049) and next prime (166878786079).

It can be written as a sum of positive squares in only one way, i.e., 94728528400 + 72150257664 = 307780^2 + 268608^2 .

It is a super-2 number, since 2×166878786064² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 119283637 + ... + 119285035.

Almost surely, 2^166878786064 is an apocalyptic number.

166878786064 is the 408508-th square number.

It is an amenable number.

166878786064 is a deficient number, since it is larger than the sum of its proper divisors (161173171229).

166878786064 is an frugal number, since it uses more digits than its factorization.

166878786064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2952 (or 1474 counting only the distinct ones).

The product of its (nonzero) digits is 130056192, while the sum is 67.

The spelling of 166878786064 in words is "one hundred sixty-six billion, eight hundred seventy-eight million, seven hundred eighty-six thousand, sixty-four".