16400420 has 24 divisors (see below), whose sum is σ = 36254400. Its totient is φ = 6214752.

The previous prime is 16400413. The next prime is 16400429. The reversal of 16400420 is 2400461.

It is not an unprimeable number, because it can be changed into a prime (16400429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21200 + ... + 21959.

It is an arithmetic number, because the mean of its divisors is an integer number (1510600).

Almost surely, 2^16400420 is an apocalyptic number.

16400420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16400420 is an abundant number, since it is smaller than the sum of its proper divisors (19853980).

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

16400420 is a wasteful number, since it uses less digits than its factorization.

16400420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43187 (or 43185 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 16400420 is about 4049.7432017351. The cubic root of 16400420 is about 254.0689873991.

Adding to 16400420 its reverse (2400461), we get a palindrome (18800881).

The spelling of 16400420 in words is "sixteen million, four hundred thousand, four hundred twenty".