168721290 has 48 divisors (see below), whose sum is σ = 439665408. Its totient is φ = 44890848.

The previous prime is 168721219. The next prime is 168721291. The reversal of 168721290 is 92127861.

168721290 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (168721291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43407 + ... + 47133.

It is an arithmetic number, because the mean of its divisors is an integer number (9159696).

Almost surely, 2^168721290 is an apocalyptic number.

168721290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

168721290 is an abundant number, since it is smaller than the sum of its proper divisors (270944118).

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

168721290 is a wasteful number, since it uses less digits than its factorization.

168721290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4243 (or 4240 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 168721290 is about 12989.2759613460. The cubic root of 168721290 is about 552.5733841907.

The spelling of 168721290 in words is "one hundred sixty-eight million, seven hundred twenty-one thousand, two hundred ninety".