225438990 has 64 divisors (see below), whose sum is σ = 650903040. Its totient is φ = 48816000.

The previous prime is 225438973. The next prime is 225438991. The reversal of 225438990 is 99834522.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225438991) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24261 + ... + 32240.

It is an arithmetic number, because the mean of its divisors is an integer number (10170360).

Almost surely, 2^225438990 is an apocalyptic number.

225438990 is an abundant number, since it is smaller than the sum of its proper divisors (425464050).

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

225438990 is a wasteful number, since it uses less digits than its factorization.

225438990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56537.

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 225438990 is about 15014.6258694647. The cubic root of 225438990 is about 608.6155019674.

The spelling of 225438990 in words is "two hundred twenty-five million, four hundred thirty-eight thousand, nine hundred ninety".