170121420 has 72 divisors (see below), whose sum is σ = 589758624. Its totient is φ = 38884608.

The previous prime is 170121403. The next prime is 170121433. The reversal of 170121420 is 24121071.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 170121393 and 170121402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66249 + ... + 68768.

It is an arithmetic number, because the mean of its divisors is an integer number (8191092).

Almost surely, 2^170121420 is an apocalyptic number.

170121420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

170121420 is an abundant number, since it is smaller than the sum of its proper divisors (419637204).

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

170121420 is a wasteful number, since it uses less digits than its factorization.

170121420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135039 (or 135034 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 170121420 is about 13043.0602237358. The cubic root of 170121420 is about 554.0976816032.

Adding to 170121420 its reverse (24121071), we get a palindrome (194242491).

The spelling of 170121420 in words is "one hundred seventy million, one hundred twenty-one thousand, four hundred twenty".