221143240 has 16 divisors (see below), whose sum is σ = 497572380. Its totient is φ = 88457280.

The previous prime is 221143231. The next prime is 221143249. The reversal of 221143240 is 42341122.

It is an interprime number because it is at equal distance from previous prime (221143231) and next prime (221143249).

It can be written as a sum of positive squares in 2 ways, for example, as 220879044 + 264196 = 14862^2 + 514^2 .

It is not an unprimeable number, because it can be changed into a prime (221143249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2764251 + ... + 2764330.

Almost surely, 2^221143240 is an apocalyptic number.

221143240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221143240 is an abundant number, since it is smaller than the sum of its proper divisors (276429140).

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

221143240 is a wasteful number, since it uses less digits than its factorization.

221143240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5528592 (or 5528588 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 221143240 is about 14870.8856494830. The cubic root of 221143240 is about 604.7249529535.

Adding to 221143240 its reverse (42341122), we get a palindrome (263484362).

It can be divided in two parts, 2211 and 43240, that added together give a triangular number (45451 = T₃₀₁).

The spelling of 221143240 in words is "two hundred twenty-one million, one hundred forty-three thousand, two hundred forty".