20403420 has 24 divisors (see below), whose sum is σ = 57129744. Its totient is φ = 5440896.

The previous prime is 20403419. The next prime is 20403431. The reversal of 20403420 is 2430402.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20403420.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169969 + ... + 170088.

It is an arithmetic number, because the mean of its divisors is an integer number (2380406).

Almost surely, 2^20403420 is an apocalyptic number.

20403420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20403420 is an abundant number, since it is smaller than the sum of its proper divisors (36726324).

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

20403420 is a wasteful number, since it uses less digits than its factorization.

20403420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340069 (or 340067 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 15.

The square root of 20403420 is about 4517.0145007516. The cubic root of 20403420 is about 273.2547100192.

Adding to 20403420 its reverse (2430402), we get a palindrome (22833822).

It can be divided in two parts, 2040 and 3420, that added together give a triangular number (5460 = T₁₀₄).

The spelling of 20403420 in words is "twenty million, four hundred three thousand, four hundred twenty".