21121131330 has 96 divisors (see below), whose sum is σ = 62618001264. Its totient is φ = 4893216768.

The previous prime is 21121131307. The next prime is 21121131337. The reversal of 21121131330 is 3313112112.

It can be written as a sum of positive squares in 8 ways, for example, as 5638057569 + 15483073761 = 75087^2 + 124431^2 .

It is a super-2 number, since 2×21121131330² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21121131337) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 511059 + ... + 550838.

Almost surely, 2^21121131330 is an apocalyptic number.

21121131330 is an abundant number, since it is smaller than the sum of its proper divisors (41496869934).

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

21121131330 is a wasteful number, since it uses less digits than its factorization.

21121131330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1061940 (or 1061937 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21121131330 its reverse (3313112112), we get a palindrome (24434243442).

The spelling of 21121131330 in words is "twenty-one billion, one hundred twenty-one million, one hundred thirty-one thousand, three hundred thirty".