168920640 has 560 divisors, whose sum is σ = 737616000. Its totient is φ = 36578304.

The previous prime is 168920639. The next prime is 168920663. The reversal of 168920640 is 46029861.

168920640 is a `hidden beast` number, since 1 + 6 + 8 + 9 + 2 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (560).

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

It is a junction number, because it is equal to n+sod(n) for n = 168920595 and 168920604.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8890551 + ... + 8890569.

Almost surely, 2^168920640 is an apocalyptic number.

168920640 is a gapful number since it is divisible by the number (10) 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 168920640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (368808000).

168920640 is an abundant number, since it is smaller than the sum of its proper divisors (568695360).

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

168920640 is an equidigital number, since it uses as much as digits as its factorization.

168920640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 168920640 is about 12996.9473338934. The cubic root of 168920640 is about 552.7909266803.

The spelling of 168920640 in words is "one hundred sixty-eight million, nine hundred twenty thousand, six hundred forty".