211020440240 has 40 divisors (see below), whose sum is σ = 516444765360. Its totient is φ = 79965639936.

The previous prime is 211020440237. The next prime is 211020440243. The reversal of 211020440240 is 42044020112.

It is an interprime number because it is at equal distance from previous prime (211020440237) and next prime (211020440243).

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×211020440240² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (211020440243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69413099 + ... + 69416138.

It is an arithmetic number, because the mean of its divisors is an integer number (12911119134).

Almost surely, 2^211020440240 is an apocalyptic number.

211020440240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211020440240 is an abundant number, since it is smaller than the sum of its proper divisors (305424325120).

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

211020440240 is a wasteful number, since it uses less digits than its factorization.

211020440240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138829269 (or 138829263 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 211020440240 its reverse (42044020112), we get a palindrome (253064460352).

The spelling of 211020440240 in words is "two hundred eleven billion, twenty million, four hundred forty thousand, two hundred forty".