20170400 has 72 divisors (see below), whose sum is σ = 51871680. Its totient is φ = 7637760.

The previous prime is 20170391. The next prime is 20170421. The reversal of 20170400 is 407102.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14537 + ... + 15863.

It is an arithmetic number, because the mean of its divisors is an integer number (720440).

Almost surely, 2^20170400 is an apocalyptic number.

20170400 is a gapful number since it is divisible by the number (20) 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 20170400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25935840).

20170400 is an abundant number, since it is smaller than the sum of its proper divisors (31701280).

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

20170400 is a wasteful number, since it uses less digits than its factorization.

20170400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1366 (or 1353 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 20170400 is about 4491.1468468533. The cubic root of 20170400 is about 272.2104772263.

Adding to 20170400 its reverse (407102), we get a palindrome (20577502).

The spelling of 20170400 in words is "twenty million, one hundred seventy thousand, four hundred".