20455420 has 36 divisors (see below), whose sum is σ = 45644760. Its totient is φ = 7698688.

The previous prime is 20455417. The next prime is 20455423. The reversal of 20455420 is 2455402.

It is an interprime number because it is at equal distance from previous prime (20455417) and next prime (20455423).

It is a junction number, because it is equal to n+sod(n) for n = 20455391 and 20455400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20455423) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4011 + ... + 7549.

It is an arithmetic number, because the mean of its divisors is an integer number (1267910).

Almost surely, 2^20455420 is an apocalyptic number.

20455420 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 20455420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22822380).

20455420 is an abundant number, since it is smaller than the sum of its proper divisors (25189340).

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

20455420 is a wasteful number, since it uses less digits than its factorization.

20455420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3582 (or 3563 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 22.

The square root of 20455420 is about 4522.7668522709. The cubic root of 20455420 is about 273.4866513766.

The spelling of 20455420 in words is "twenty million, four hundred fifty-five thousand, four hundred twenty".