225021420 has 288 divisors, whose sum is σ = 794731392. Its totient is φ = 51093504.

The previous prime is 225021409. The next prime is 225021421. The reversal of 225021420 is 24120522.

225021420 is a `hidden beast` number, since 22 + 502 + 142 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 225021393 and 225021402.

It is not an unprimeable number, because it can be changed into a prime (225021421) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1991284 + ... + 1991396.

It is an arithmetic number, because the mean of its divisors is an integer number (2759484).

Almost surely, 2^225021420 is an apocalyptic number.

225021420 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 225021420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (397365696).

225021420 is an abundant number, since it is smaller than the sum of its proper divisors (569709972).

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

225021420 is a wasteful number, since it uses less digits than its factorization.

225021420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201 (or 196 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 225021420 is about 15000.7139830076. The cubic root of 225021420 is about 608.2394997992.

Adding to 225021420 its reverse (24120522), we get a palindrome (249141942).

The spelling of 225021420 in words is "two hundred twenty-five million, twenty-one thousand, four hundred twenty".