221125640 has 16 divisors (see below), whose sum is σ = 497532780. Its totient is φ = 88450240.

The previous prime is 221125631. The next prime is 221125643. The reversal of 221125640 is 46521122.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 219573124 + 1552516 = 14818^2 + 1246^2 .

It is not an unprimeable number, because it can be changed into a prime (221125643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2764031 + ... + 2764110.

Almost surely, 2^221125640 is an apocalyptic number.

221125640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221125640 is an abundant number, since it is smaller than the sum of its proper divisors (276407140).

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

221125640 is a wasteful number, since it uses less digits than its factorization.

221125640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5528152 (or 5528148 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 221125640 is about 14870.2938773919. The cubic root of 221125640 is about 604.7089098955.

Adding to 221125640 its reverse (46521122), we get a palindrome (267646762).

The spelling of 221125640 in words is "two hundred twenty-one million, one hundred twenty-five thousand, six hundred forty".