21011121331984 has 20 divisors (see below), whose sum is σ = 46524625806784. Its totient is φ = 9004766285088.

The previous prime is 21011121331957. The next prime is 21011121331987. The reversal of 21011121331984 is 48913312111012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21011121331987) 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, 93799648692 + ... + 93799648915.

Almost surely, 2^{21011121331984} is an apocalyptic number.

It is an amenable number.

21011121331984 is an abundant number, since it is smaller than the sum of its proper divisors (25513504474800).

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

21011121331984 is a wasteful number, since it uses less digits than its factorization.

21011121331984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187599297622 (or 187599297616 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 37.

Adding to 21011121331984 its reverse (48913312111012), we get a palindrome (69924433442996).

The spelling of 21011121331984 in words is "twenty-one trillion, eleven billion, one hundred twenty-one million, three hundred thirty-one thousand, nine hundred eighty-four".