221142540 has 48 divisors (see below), whose sum is σ = 625599072. Its totient is φ = 58361856.

The previous prime is 221142533. The next prime is 221142583. The reversal of 221142540 is 45241122.

221142540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13179 + ... + 24818.

It is an arithmetic number, because the mean of its divisors is an integer number (13033314).

Almost surely, 2^221142540 is an apocalyptic number.

221142540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221142540 is an abundant number, since it is smaller than the sum of its proper divisors (404456532).

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

221142540 is a wasteful number, since it uses less digits than its factorization.

221142540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38106 (or 38104 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 221142540 is about 14870.8621135427. The cubic root of 221142540 is about 604.7243148936.

Adding to 221142540 its reverse (45241122), we get a palindrome (266383662).

The spelling of 221142540 in words is "two hundred twenty-one million, one hundred forty-two thousand, five hundred forty".