163989720 has 48 divisors (see below), whose sum is σ = 532967760. Its totient is φ = 43730496.

The previous prime is 163989697. The next prime is 163989773. The reversal of 163989720 is 27989361.

163989720 is a `hidden beast` number, since 1 + 639 + 8 + 9 + 7 + 2 + 0 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 227404 + ... + 228123.

It is an arithmetic number, because the mean of its divisors is an integer number (11103495).

Almost surely, 2^163989720 is an apocalyptic number.

163989720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

163989720 is an abundant number, since it is smaller than the sum of its proper divisors (368978040).

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

163989720 is a wasteful number, since it uses less digits than its factorization.

163989720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455544 (or 455537 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 163989720 is about 12805.8471020077. The cubic root of 163989720 is about 547.3589303153.

The spelling of 163989720 in words is "one hundred sixty-three million, nine hundred eighty-nine thousand, seven hundred twenty".