21115235320552 has 8 divisors (see below), whose sum is σ = 39591066226050. Its totient is φ = 10557617660272.

The previous prime is 21115235320549. The next prime is 21115235320561. The reversal of 21115235320552 is 25502353251112.

It can be written as a sum of positive squares in only one way, i.e., 20662352083396 + 452883237156 = 4545586^2 + 672966^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319702207527 + ... + 1319702207542.

Almost surely, 2^{21115235320552} is an apocalyptic number.

It is an amenable number.

21115235320552 is a deficient number, since it is larger than the sum of its proper divisors (18475830905498).

21115235320552 is a wasteful number, since it uses less digits than its factorization.

21115235320552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2639404415075 (or 2639404415071 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 37.

Adding to 21115235320552 its reverse (25502353251112), we get a palindrome (46617588571664).

The spelling of 21115235320552 in words is "twenty-one trillion, one hundred fifteen billion, two hundred thirty-five million, three hundred twenty thousand, five hundred fifty-two".