1666700172 has 48 divisors (see below), whose sum is σ = 4365649120. Its totient is φ = 549835776.

The previous prime is 1666700171. The next prime is 1666700173. The reversal of 1666700172 is 2710076661.

It is an interprime number because it is at equal distance from previous prime (1666700171) and next prime (1666700173).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1666700171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69073 + ... + 90024.

Almost surely, 2^1666700172 is an apocalyptic number.

1666700172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1666700172 is an abundant number, since it is smaller than the sum of its proper divisors (2698948948).

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

1666700172 is a wasteful number, since it uses less digits than its factorization.

1666700172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159207 (or 159199 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 1666700172 is about 40825.2393991756. The cubic root of 1666700172 is about 1185.6390464365.

The spelling of 1666700172 in words is "one billion, six hundred sixty-six million, seven hundred thousand, one hundred seventy-two".