20331420 has 24 divisors (see below), whose sum is σ = 56928144. Its totient is φ = 5421696.

The previous prime is 20331419. The next prime is 20331461. The reversal of 20331420 is 2413302.

20331420 = T₉₂₈ + T₉₂₉ + ... + T₉₇₂.

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 20331420.

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, 169369 + ... + 169488.

It is an arithmetic number, because the mean of its divisors is an integer number (2372006).

Almost surely, 2^20331420 is an apocalyptic number.

20331420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20331420 is an abundant number, since it is smaller than the sum of its proper divisors (36596724).

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

20331420 is a wasteful number, since it uses less digits than its factorization.

20331420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338869 (or 338867 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 20331420 is about 4509.0375913270. The cubic root of 20331420 is about 272.9329089518.

Adding to 20331420 its reverse (2413302), we get a palindrome (22744722).

The spelling of 20331420 in words is "twenty million, three hundred thirty-one thousand, four hundred twenty".