1240221811 has 4 divisors (see below), whose sum is σ = 1241524152. Its totient is φ = 1238919472.

The previous prime is 1240221809. The next prime is 1240221821. The reversal of 1240221811 is 1181220421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1181220421 = 6287 ⋅187883.

It is a cyclic number.

It is not a de Polignac number, because 1240221811 - 2¹ = 1240221809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1240221821) 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, 649741 + ... + 651646.

It is an arithmetic number, because the mean of its divisors is an integer number (310381038).

Almost surely, 2^1240221811 is an apocalyptic number.

1240221811 is a deficient number, since it is larger than the sum of its proper divisors (1302341).

1240221811 is an equidigital number, since it uses as much as digits as its factorization.

1240221811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1302340.

The product of its (nonzero) digits is 256, while the sum is 22.

The square root of 1240221811 is about 35216.7830870453. The cubic root of 1240221811 is about 1074.4011262504.

The spelling of 1240221811 in words is "one billion, two hundred forty million, two hundred twenty-one thousand, eight hundred eleven".