225212021 has 8 divisors (see below), whose sum is σ = 236857344. Its totient is φ = 213721200.

The previous prime is 225212017. The next prime is 225212023. The reversal of 225212021 is 120212522.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 225212021 - 2² = 225212017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225212023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35630 + ... + 41471.

It is an arithmetic number, because the mean of its divisors is an integer number (29607168).

Almost surely, 2^225212021 is an apocalyptic number.

It is an amenable number.

225212021 is a deficient number, since it is larger than the sum of its proper divisors (11645323).

225212021 is a wasteful number, since it uses less digits than its factorization.

225212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77251.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 225212021 is about 15007.0657025283. The cubic root of 225212021 is about 608.4111846989.

Adding to 225212021 its reverse (120212522), we get a palindrome (345424543).

It can be divided in two parts, 22521 and 2021, that added together give a palindrome (24542).

The spelling of 225212021 in words is "two hundred twenty-five million, two hundred twelve thousand, twenty-one".