212531440 has 40 divisors (see below), whose sum is σ = 539059248. Its totient is φ = 77283840.

The previous prime is 212531383. The next prime is 212531447. The reversal of 212531440 is 44135212.

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

It is a super-2 number, since 2×212531440² = 90339225976947200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212531447) 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, 119877 + ... + 121636.

Almost surely, 2^212531440 is an apocalyptic number.

212531440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212531440 is an abundant number, since it is smaller than the sum of its proper divisors (326527808).

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

212531440 is a wasteful number, since it uses less digits than its factorization.

212531440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241537 (or 241531 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 212531440 is about 14578.4580803321. The cubic root of 212531440 is about 596.7710244038.

Adding to 212531440 its reverse (44135212), we get a palindrome (256666652).

The spelling of 212531440 in words is "two hundred twelve million, five hundred thirty-one thousand, four hundred forty".