21115653533436 has 144 divisors (see below), whose sum is σ = 62526677697792. Its totient is φ = 5484374380800.

The previous prime is 21115653533431. The next prime is 21115653533453. The reversal of 21115653533436 is 63433535651112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115653533431) 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, 237725745 + ... + 237814551.

It is an arithmetic number, because the mean of its divisors is an integer number (434213039568).

Almost surely, 2^{21115653533436} is an apocalyptic number.

It is an amenable number.

21115653533436 is an abundant number, since it is smaller than the sum of its proper divisors (41411024164356).

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

21115653533436 is a wasteful number, since it uses less digits than its factorization.

21115653533436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125600 (or 125591 counting only the distinct ones).

The product of its digits is 2916000, while the sum is 48.

The spelling of 21115653533436 in words is "twenty-one trillion, one hundred fifteen billion, six hundred fifty-three million, five hundred thirty-three thousand, four hundred thirty-six".