210121031440 has 20 divisors (see below), whose sum is σ = 488531398284. Its totient is φ = 84048412544.

The previous prime is 210121031411. The next prime is 210121031539. The reversal of 210121031440 is 44130121012.

It can be written as a sum of positive squares in 2 ways, for example, as 150879418624 + 59241612816 = 388432^2 + 243396^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1313256367 + ... + 1313256526.

Almost surely, 2^210121031440 is an apocalyptic number.

210121031440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210121031440 is an abundant number, since it is smaller than the sum of its proper divisors (278410366844).

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

210121031440 is a wasteful number, since it uses less digits than its factorization.

210121031440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2626512906 (or 2626512900 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 210121031440 its reverse (44130121012), we get a palindrome (254251152452).

The spelling of 210121031440 in words is "two hundred ten billion, one hundred twenty-one million, thirty-one thousand, four hundred forty".