166684738380840 has 128 divisors (see below), whose sum is σ = 555705015264000. Its totient is φ = 44442125915904.

The previous prime is 166684738380827. The next prime is 166684738380851. The reversal of 166684738380840 is 48083837486661.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5661324 + ... + 19115963.

It is an arithmetic number, because the mean of its divisors is an integer number (4341445431750).

Almost surely, 2^{166684738380840} is an apocalyptic number.

166684738380840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166684738380840 is an abundant number, since it is smaller than the sum of its proper divisors (389020276883160).

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

166684738380840 is a wasteful number, since it uses less digits than its factorization.

166684738380840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24783536 (or 24783526 counting only the distinct ones).

The product of its (nonzero) digits is 891813888, while the sum is 72.

The spelling of 166684738380840 in words is "one hundred sixty-six trillion, six hundred eighty-four billion, seven hundred thirty-eight million, three hundred eighty thousand, eight hundred forty".