166721472 has 84 divisors (see below), whose sum is σ = 493345216. Its totient is φ = 53775360.

The previous prime is 166721461. The next prime is 166721483. The reversal of 166721472 is 274127661.

166721472 is a `hidden beast` number, since 166 + 7 + 21 + 472 = 666.

It is an interprime number because it is at equal distance from previous prime (166721461) and next prime (166721483).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13188 + ... + 22524.

Almost surely, 2^166721472 is an apocalyptic number.

166721472 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166721472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246672608).

166721472 is an abundant number, since it is smaller than the sum of its proper divisors (326623744).

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

166721472 is a wasteful number, since it uses less digits than its factorization.

166721472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9386 (or 9373 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 166721472 is about 12912.0669143248. The cubic root of 166721472 is about 550.3815226130.

The spelling of 166721472 in words is "one hundred sixty-six million, seven hundred twenty-one thousand, four hundred seventy-two".